TL;DR: How Long Does AI Development Take? 

Most AI projects take between 6 weeks and 12 months from kickoff to production. A chatbot or retrieval assistant built on an existing foundation model typically ships in 6 to 10 weeks. A custom machine learning model trained on proprietary data usually takes 3 to 5 months. Enterprise-grade AI platforms with multiple models, regulatory requirements, and deep system integration run 6 to 12 months, sometimes longer. The single biggest variable is not model complexity. It is data readiness. Teams with clean, labelled, accessible data move two to three times faster than teams that discover their data problems in week four. These ranges are based on delivery experience at Aalpha, an AI development company that has built AI and machine learning systems for clients across 45+ countries since 2008.

Key takeaways

  • AI development timelines are driven by seven phases, and only two of them involve model building. The rest is discovery, data work, integration, evaluation, and deployment.
  • Data preparation consumes 25 to 40 percent of the total project calendar on custom ML work. It is the phase most often underestimated.
  • Choosing an API-based approach over training from scratch can cut the timeline by 70 percent, with tradeoffs in control and unit economics.
  • A proof of concept is not a smaller version of a production system. Conflating the two is the most common cause of schedule overrun.
  • Regulatory load, particularly in healthcare, finance, and any workload touching personal data under GDPR or India’s DPDP Act, adds 3 to 8 weeks of compliance and documentation work.
  • Timelines do not end at launch. Retraining, drift monitoring, and evaluation cycles are permanent commitments, typically 15 to 25 percent of the original build effort per year.

What an AI development timeline actually covers

Ask three vendors how long an AI project takes and you will get three answers that differ by months. That is rarely because one of them is lying. It is because they are measuring different things.

Where the clock starts

Some estimates begin the moment a developer opens a code editor. That is the wrong starting point and it is why so many projects appear to slip. The realistic clock starts at discovery: the sessions where you establish what problem the model is meant to solve, what success looks like numerically, what data exists, and who owns it. On a mid-sized project this phase alone runs 1 to 3 weeks, and skipping it does not save time. It defers the cost to a later phase where it is more expensive to absorb.

The clock also starts before data access is granted. In enterprises, getting read permissions on a production database can take longer than building the model that consumes it. If your estimate does not budget for procurement, security review, and data governance sign-off, it is not an estimate. It is a hope.

Where the clock stops

Deployment day is not the finish line. An AI system that has been pushed to production but has no monitoring, no retraining pipeline, no feedback capture, and no rollback plan is an unfinished system. It will degrade. The honest timeline includes the two to four weeks after go-live where the team watches real traffic, catches the failure modes that no test set surfaced, and tunes thresholds.

For the purposes of this guide, a complete AI development timeline runs from discovery kickoff to a stable production system with monitoring in place and a documented retraining cadence.

Why estimates vary so much between vendors

Four things usually explain the gap:

  1. Scope of the finish line. One vendor is quoting a proof of concept, another is quoting production. These can differ by a factor of four.
  2. Assumed data condition. A quote that assumes clean, labelled, structured data will always look cheaper and faster than one that budgets for data engineering.
  3. Build approach. API integration, retrieval augmentation, fine-tuning, and training from scratch sit on a very wide timeline spectrum.
  4. Integration surface. A standalone model is fast. A model that must read from four internal systems and write to two more is a systems integration project that happens to contain a model.

When you are comparing proposals, normalise these four variables first. Otherwise you are comparing numbers that describe different projects.

AI development timeline at a glance

The table below gives realistic end-to-end durations for common project types, assuming a competent team and reasonably cooperative data. Add 30 to 50 percent if the data is unstructured, unlabelled, or spread across systems that do not talk to each other.

Project type

Typical duration

Core team size

Primary timeline driver

Prompt-based assistant on an existing LLM API

3 to 6 weeks

2 to 3

Integration and prompt evaluation

RAG assistant over internal documents

6 to 10 weeks

3 to 4

Document ingestion and retrieval quality

Workflow automation with agentic steps

10 to 16 weeks

4 to 5

Tool integration and failure handling

Document processing and intelligent OCR

8 to 14 weeks

3 to 5

Template variance and accuracy threshold

Predictive analytics model

12 to 20 weeks

4 to 6

Historical data quality and feature engineering

Recommendation engine

14 to 22 weeks

4 to 6

Event data volume and cold start handling

Computer vision system

16 to 28 weeks

5 to 7

Image collection and annotation volume

Fine-tuned domain-specific LLM

12 to 24 weeks

4 to 6

Training data curation and evaluation design

Enterprise AI platform, multi-model

26 to 52 weeks

8 to 15

Governance, integration, and change management

Foundation model trained from scratch

12 to 24 months

15+

Compute budget and research risk

Two notes on reading this table. First, these are calendar durations, not effort estimates. A 10-week project with a team of four is roughly 1,600 hours of work, not 400. Second, the ranges assume the client can make decisions in days rather than weeks. Slow stakeholder feedback is the most common source of unbudgeted delay, and it is entirely within the client’s control.

The seven phases of AI development and how long each takes

Almost every AI project, regardless of type, moves through the same seven phases. What changes is the weight of each phase. Understanding where the time actually goes is the difference between a plan and a guess.

Phase 1: Discovery and feasibility (1 to 4 weeks)

This phase answers three questions. Is the problem solvable with the data available? Is it worth solving? And what does “working” mean in numbers?

The output should include a written problem statement, a target metric with a threshold (not “accurate” but “at least 92 percent precision on invoice line item extraction”), a data inventory listing what exists and where, and a feasibility verdict. On regulated projects, add an initial compliance assessment here.

What makes it run long: unclear ownership of the problem, multiple stakeholders with conflicting definitions of success, or a data inventory that reveals the required data does not exist yet. That last one is common and it is better to find it in week two than week twelve.

How to compress it: run discovery as a focused workshop series rather than a series of scattered meetings. Three intensive sessions across two weeks beats eight meetings across six weeks.

Phase 2: Data acquisition and preparation (2 to 12 weeks)

This is the phase that eats timelines. On custom machine learning projects it routinely consumes 25 to 40 percent of the total calendar, and it is the phase most likely to be underestimated in a proposal.

The work includes locating and extracting data from source systems, cleaning and deduplicating it, handling missing values, engineering features, splitting into training, validation and test sets, and where supervised learning is involved, labelling.

Labelling deserves its own mention. Annotating 10,000 images for object detection is not a week of work. At a realistic rate of 60 to 120 images per hour per annotator, with a quality review pass, that is 150 to 250 hours before review. Text classification is faster. Medical image segmentation is dramatically slower and requires clinicians, not general annotators.

What makes it run long: data spread across systems with no documentation, personally identifiable information that needs anonymisation, class imbalance requiring collection of additional examples, and label disagreement between annotators that forces the team to rewrite the annotation guidelines mid-flight.

How to compress it: start data access requests during discovery rather than after it. Use synthetic data augmentation where the domain allows. Use pre-trained models that need fewer examples. Where labelling is unavoidable, run a 200-example pilot first to validate the annotation guidelines before committing to the full volume.

Phase 3: Model selection and proof of concept (2 to 5 weeks)

Here the team establishes that the approach works before committing to building it properly. Two or three candidate approaches are tried against a held-out sample, results are compared, and one is chosen.

The deliverable is not a product. It is evidence, usually a notebook, a metrics comparison, and a written recommendation. Treating the POC notebook as the foundation of the production system is a well-known way to inherit six weeks of technical debt.

What makes it run long: trying too many approaches, or an unstated accuracy target that means nobody can agree whether the POC succeeded.

How to compress it: timebox it. Two weeks, three approaches, one decision. If none of the three clears the threshold, that is a valid and useful outcome that should trigger a scope conversation, not a silent extension.

Phase 4: Model development and training (3 to 10 weeks)

The phase everyone imagines when they think of AI development, and usually not the longest one.

Work includes building the training pipeline, running experiments, tuning hyperparameters, tracking runs, and iterating toward the target metric. For fine-tuning work, this includes curating the instruction dataset and running evaluation after each training run. For retrieval systems, it includes chunking strategy, embedding model selection, index configuration, and reranking.

Training compute time is often a smaller factor than people expect. A fine-tune on a mid-sized open model can complete in hours. The calendar time goes into the iteration loop: train, evaluate, diagnose, adjust, repeat. Each cycle on a serious project takes one to three days.

What makes it run long: chasing marginal accuracy gains past the point of business value, insufficient compute causing queueing, and evaluation sets that are too small to distinguish real improvement from noise.

How to compress it: define the accuracy threshold in phase one and stop when you hit it. Build the evaluation harness before the first training run, not after.

Phase 5: System and API integration (2 to 8 weeks)

The model becomes a service that other systems can call. This means API design, authentication, rate limiting, caching, queueing for long-running inference, error handling, and connecting to the systems that supply inputs and consume outputs.

This phase is frequently underestimated because it is not glamorous. It is also where most of the surprises live. Legacy systems with undocumented APIs, rate limits on third-party services, data format mismatches, and network policies that block outbound calls to model providers are all routine.

What makes it run long: the number of systems in the integration surface, and the age of those systems. Every additional integration point adds days, not hours.

How to compress it: map the integration surface during discovery and confirm API access early. Build against a mock of the slowest integration so work does not stall waiting for access.

Phase 6: Evaluation, testing and hardening (2 to 6 weeks)

Traditional software testing plus AI-specific evaluation. The AI-specific work includes measuring performance across data slices to catch subgroup failures, adversarial and edge case testing, hallucination and grounding checks for generative systems, bias assessment, and human review of a representative output sample.

For generative AI in particular, this phase has grown. Automated metrics only tell you so much, so teams build evaluation sets with human-graded reference answers and run structured comparisons after every meaningful change.

What makes it run long: discovering a systematic failure on an important subgroup that requires returning to phase two for more data. This is why slice-based evaluation should start during phase four, not phase six.

How to compress it: start building the evaluation set during data preparation. Automate what can be automated so regression testing after each change costs minutes rather than days.

Phase 7: Deployment and MLOps (2 to 6 weeks)

Getting the system into production and keeping it healthy. Containerisation, infrastructure provisioning, CI/CD, model registry and versioning, monitoring for latency, cost, error rate and drift, logging for auditability, alerting, and a rollback path.

If the organisation already has mature MLOps infrastructure, this compresses considerably. If this is the first model going into production, treat it as a platform-building exercise and budget accordingly, because the next model will benefit from everything built here.

What makes it run long: first-time infrastructure, security review cycles, and production environments that differ materially from staging.

How to compress it: provision the production environment during phase four so it is ready and reviewed by the time the model is. Deploy a trivial placeholder model to production early to prove the pipeline end to end.

How the phases overlap

Sequential phase diagrams are useful for explanation and misleading for planning. In practice, data preparation overlaps with model selection, integration work starts while training is still iterating, and evaluation harness construction runs alongside data work. A realistic plan has three or four workstreams running in parallel with defined sync points.

The phases that genuinely cannot be parallelised are discovery before everything else, and evaluation before deployment. Everything else can be overlapped by a team that plans for it.

AI development timelines by project type

Phase durations shift depending on what you are building. Below are realistic timelines for the project types clients ask about most often, with the reasoning behind each range.

Chatbot or RAG assistant (6 to 10 weeks)

A retrieval-augmented assistant over internal documents is currently the most requested AI build, and the most predictable.

The heavy work is not the model. It is document ingestion: handling PDFs with inconsistent structure, scanned files needing OCR, tables that lose meaning when flattened to text, and access control so users only retrieve documents they are permitted to see. Retrieval quality tuning, chunk sizing, embedding choice, hybrid search, and reranking typically takes two to three weeks of iteration on its own.

Add two to four weeks if the assistant needs to take actions rather than only answer questions, because that turns it into an agentic system with a different failure profile.

Computer vision system (16 to 28 weeks)

Vision timelines are dominated by data. If a usable annotated dataset exists, the timeline compresses sharply. If images must be collected from the field, which is normal for quality inspection, retail shelf monitoring, or safety compliance, expect 4 to 10 weeks of collection and annotation before meaningful training begins.

Edge deployment adds further time. A model that runs in a data centre is a different engineering problem from one that must run on a device with limited memory and no reliable network. Quantisation, pruning, and hardware-specific optimisation add 3 to 6 weeks.

Predictive analytics and forecasting (12 to 20 weeks)

Demand forecasting, churn prediction, credit risk scoring, and predictive maintenance share a common shape. Feature engineering dominates. Historical data must be assembled at the right granularity, leakage must be eliminated, and seasonality and external factors must be represented.

A specific trap here is temporal validation. Splitting time series data randomly instead of chronologically produces beautiful validation results and a model that fails in production. Catching this late costs weeks.

Recommendation engine (14 to 22 weeks)

The model itself is well-understood. The time goes into event data pipelines, cold start strategy for new users and new items, real-time serving with acceptable latency, and building the A/B testing infrastructure needed to prove the system actually improves the business metric.

If clickstream and interaction events are not already being captured cleanly, add 4 to 8 weeks for instrumentation before anything can be trained.

Document processing and intelligent OCR (8 to 14 weeks)

Invoice extraction, KYC document processing, contract analysis, and claims intake. The range is wide because it depends almost entirely on template variance. Ten known layouts is a very different project from a thousand unknown ones.

The accuracy threshold matters enormously here. Ninety percent field-level accuracy is reachable quickly. Ninety-eight percent, which is what finance teams usually need, requires a validation and human-in-the-loop layer that can double the integration effort.

Agentic workflow automation (10 to 16 weeks)

Systems that plan and execute multi-step tasks across tools. The model work is modest. The engineering work is substantial: tool definitions, permission scoping, state management, retry and failure handling, cost control, and guardrails preventing the agent from taking destructive actions.

Evaluation is harder than in other project types because success is a trajectory rather than a single output. Building the evaluation approach is itself a two-week task.

Fine-tuned domain LLM (12 to 24 weeks)

Justified when the domain language is genuinely specialised, when latency or unit cost rules out large API models, or when data residency requires self-hosting.

Timeline is driven by training data curation. A quality instruction dataset of a few thousand examples, reviewed by domain experts, is weeks of work involving people whose time is expensive and scarce. Self-hosting then adds inference infrastructure work that API-based approaches avoid entirely.

Worth stating plainly: most organisations that ask for fine-tuning are better served by retrieval, better prompting, and structured evaluation. Fine-tuning is a real tool but it is often reached for too early.

How your build approach changes the timeline

Before any phase planning happens, one decision sets the outer bound on how fast the project can move. It is the choice between using a model, adapting a model, and building a model. Clients consistently underestimate how large this lever is.

Option 1: Third-party API integration (3 to 8 weeks)

Calling a hosted model from a provider such as Anthropic, OpenAI, or Google. No training, no inference infrastructure, no ML engineering in the traditional sense.

The work is prompt design, structured output handling, evaluation, integration, cost control, and fallback behaviour when the provider is slow or unavailable. This is a software engineering project with an AI component, and it is why capable teams ship useful AI features in under two months.

Tradeoffs: recurring per-token cost that scales with usage, dependency on a provider’s roadmap and pricing, data residency questions, and limited control over model behaviour changes when providers update versions.

Option 2: Retrieval augmentation on top of a foundation model (6 to 12 weeks)

The default architecture for making a general model useful on private data. Documents are indexed, relevant passages are retrieved at query time, and the model answers grounded in them.

Adds ingestion pipelines, vector storage, retrieval tuning, and permission handling to the API timeline. In exchange it gives current, auditable, source-attributed answers without training anything. For the large majority of “we want an AI that knows our business” requests, this is the correct answer.

Option 3: Fine-tuning an existing model (10 to 20 weeks)

Taking a pre-trained model and continuing training on domain data to change its behaviour, style, or format adherence.

Adds training data curation, training runs, evaluation against the base model, and if self-hosted, inference infrastructure. The timeline addition over RAG is meaningful and the benefit is narrower than most buyers expect. Fine-tuning teaches form and behaviour well. It teaches facts poorly, which is the thing people usually want it for.

Option 4: Training a custom model from scratch (5 months to 2 years)

Building a model architecture and training it on your own data from random initialisation. For classical machine learning on tabular data this is entirely normal and takes months, not years. For deep learning on language or vision it means a research programme with meaningful failure risk.

Justified when no suitable pre-trained model exists for the domain, when the data modality is unusual, or when the model itself is the commercial product. Not justified because it sounds more impressive.

Comparing the four approaches

Approach

Timeline

Upfront cost

Running cost

Control

Best fit

API integration

3 to 8 weeks

Lowest

Per-token, scales with use

Low

Fast time to value, variable volume

Retrieval augmentation

6 to 12 weeks

Low to moderate

Per-token plus storage

Moderate

Private knowledge, need for citations

Fine-tuning

10 to 20 weeks

Moderate to high

Hosting or per-token

High

Specialised style, format, or latency needs

Training from scratch

5 to 24 months

Highest

Infrastructure

Total

Novel domain, model as the product

A practical sequencing recommendation: start at the top of this table and move down only when you have evidence the simpler approach is insufficient. Teams that begin at option three routinely spend four months arriving at a result option two would have delivered in eight weeks.

Factors that stretch or compress the timeline

Two projects with identical scope can differ by three months. These are the variables that explain the gap, roughly in order of impact.

Data readiness

The dominant factor. A useful way to assess it before committing to a date:

  • Green (adds nothing): data is centralised, documented, labelled where needed, and access is already granted.
  • Amber (adds 2 to 6 weeks): data exists but is spread across systems, partially documented, needs cleaning, and access requires internal approval.
  • Red (adds 6 to 16 weeks): data must be collected or generated, labelling has not started, or quality is unknown because nobody has audited it.

Most organisations believe they are green and are amber. A two-day data audit during discovery is the highest-return activity in the entire project.

Integration surface area

Count the systems the AI must read from or write to. Each one adds roughly 3 to 8 days depending on API quality and documentation. A model that must touch a CRM, an ERP, a document store, and a messaging platform is carrying a month of integration work before anyone considers the model itself.

Older systems compound this. A SOAP interface with no sandbox environment can consume more time than three modern REST integrations.

Regulatory and compliance requirements

Healthcare, financial services, insurance, and any system processing personal data carry documentation and review burdens that sit outside engineering.

Typical additions: HIPAA-aligned work adds 3 to 6 weeks for controls, audit logging, and business associate agreements. GDPR and India’s DPDP Act add 2 to 4 weeks for data mapping, lawful basis documentation, retention policy, and subject access handling. The EU AI Act adds risk classification, technical documentation, and conformity work for high-risk categories, which for a first-time build can mean 4 to 8 weeks. Financial services model risk management adds independent validation cycles that are scheduled by a committee rather than by your project plan.

Plan compliance work in parallel from week one. Treating it as a pre-launch gate is how projects lose a month at the worst possible moment.

Accuracy threshold

The relationship between accuracy and effort is not linear. Reaching 85 percent on a well-defined task might take three weeks. Reaching 95 percent might take three months. Reaching 99 percent might not be possible with the available data at all.

The correct question is not “how accurate can it be” but “how accurate does it need to be for the workflow to be viable, and what does the system do when it is uncertain”. A model at 92 percent with a clean escalation path to a human often delivers more business value than a model at 97 percent with no escalation path, and it ships two months earlier.

Stakeholder decision speed

The most underrated factor and the one clients control entirely. A project needing 15 decisions moves at a completely different pace when decisions take one day versus one week. That difference alone is six to eight weeks on a typical mid-sized build.

Nominate one decision owner with authority. Agree a maximum turnaround for feedback. Schedule recurring review slots rather than requesting meetings reactively.

Team experience and composition

A team that has shipped three similar systems moves roughly twice as fast as a capable team doing it for the first time, mostly by avoiding known dead ends. This is not about raw skill. It is about pattern recognition on failure modes.

Scope stability

Every scope change after phase three costs more than it would have cost in phase one, and the multiplier grows. A requirement added during evaluation can force a return to data preparation, invalidating weeks of work. Fix scope at the end of discovery and route additions to a defined phase two rather than absorbing them silently.

POC, pilot, MVP and production are four different finish lines

A large share of timeline disputes come from a scoping ambiguity rather than a delivery failure. The vendor delivered what was agreed and the client expected something four times larger. These four terms are not interchangeable.

Proof of concept (2 to 6 weeks)

Question it answers: is this technically possible with our data?

Runs on a sample dataset, often in a notebook, with no production infrastructure, no integration, no user interface beyond a basic demo. Evaluated on a metric, not on user experience.

Success criteria: a documented yes or no with evidence. A POC that returns “no” is a successful POC and has saved considerable money.

Pilot (6 to 12 weeks)

Question it answers: does it work in real conditions with real users?

A limited deployment to a controlled group with real data, basic monitoring, and structured feedback collection. Not fully hardened, not fully integrated, but genuinely used.

Success criteria: measured impact on the target business metric plus qualitative feedback from real users.

Minimum viable product (10 to 20 weeks)

Question it answers: can this deliver value in a form users will adopt?

Production-deployed with a narrowed feature set, proper integration for the core workflow, monitoring, error handling, and support processes. Real users depend on it.

Success criteria: adoption and retained usage, plus stability metrics.

Production system (16 to 40 weeks)

Question it answers: can this operate reliably at scale as core infrastructure?

Full feature set, full integration, redundancy, security review passed, compliance documentation complete, retraining pipeline operational, runbooks written, support model defined.

Success criteria: service level targets met consistently under real load.

Choosing the right finish line

For a genuinely uncertain problem, sequence POC then pilot then MVP. For a well-understood problem with a proven pattern, going straight to build MVP is faster and cheaper because the POC would only confirm what is already known.

The mistake to avoid is running a POC and then treating the POC codebase as the MVP foundation. POC code is written to answer a question quickly, not to be maintained. Budget for the rewrite or accept the debt knowingly.

Team composition and its effect on duration

Duration is not simply effort divided by headcount. AI projects have sequential dependencies that resist parallelisation, and adding people to certain phases actively slows them down.

Roles on a typical AI project

Role

Involved during

Effect of adding a second one

Product or business analyst

Discovery, evaluation criteria

Marginal, can reduce clarity

Data engineer

Data acquisition and preparation

High, this phase parallelises well

ML or AI engineer

Model selection, development

Moderate, useful for parallel experiments

Backend engineer

Integration, serving

High, independent workstreams

MLOps or platform engineer

Deployment, monitoring

Low to moderate

QA engineer

Evaluation, testing

Moderate, especially for evaluation set building

Domain expert

Labelling, evaluation review

Very high, usually the bottleneck

Project manager

Throughout

None, one is correct

Where adding people compresses the timeline

Data annotation is the clearest case. Doubling annotators roughly halves annotation calendar time, provided the guidelines are stable and quality review scales with them.

Integration work parallelises well when the systems are independent. Two engineers on two separate integrations is close to twice as fast.

Running multiple model experiments concurrently helps during phase three, assuming compute is available.

Where adding people does not help

Architecture decisions, evaluation set design, and debugging a specific model failure are single-owner activities. More people means more discussion and slower convergence.

The domain expert is very often the real constraint. If one clinician, one underwriter, or one senior engineer must review every labelled example and answer every question, the project moves at the speed of their availability regardless of how many engineers are on it. Identify this person in week one and secure a committed time allocation, in writing.

A realistic staffing curve

Team size should not be flat. A typical 16-week project ramps roughly as follows: two people in discovery, four to five during data preparation and early modelling, five to six during integration and evaluation, then back to three for deployment and stabilisation. Staffing flat at peak size wastes budget in the early and late phases.

Three worked timeline examples

Abstract ranges are less useful than concrete plans. Here are three real-shaped projects with week-by-week structure.

Example 1: RAG assistant for an internal knowledge base (8 weeks)

A mid-sized services company wants an assistant that answers policy and process questions from around 4,000 internal documents held in SharePoint.

Weeks

Focus

Deliverables

1

Discovery

Use cases, success metric, document inventory, access confirmed

2

Ingestion pipeline

Document extraction, chunking, first index built

3

Retrieval tuning

Embedding comparison, hybrid search, reranking, retrieval metrics

4

Answer generation

Prompt design, citation formatting, refusal behaviour for out-of-scope questions

5

Interface and access control

Chat interface, permission-aware retrieval, conversation history

6

Evaluation

150-question evaluation set, human-graded reference answers, accuracy measurement

7

Hardening

Edge cases, rate limiting, cost controls, logging

8

Deployment

Production release, monitoring, feedback capture, handover

Why this can be 8 weeks: no model training, documents already centralised in one system, single integration point, accuracy threshold defined as “correct and cited on 90 percent of evaluation questions”.

What would make it 14 weeks: documents spread across four systems including scanned PDFs, a requirement to take actions rather than only answer, or a compliance review cycle.

Example 2: Computer vision quality inspection (18 weeks)

A manufacturer wants automated detection of surface defects on a production line, running on edge hardware beside the conveyor.

Weeks

Focus

Deliverables

1 to 2

Discovery and feasibility

Defect taxonomy, accuracy and latency targets, camera and lighting assessment

3 to 6

Image collection

Camera rig installed, 12,000 images captured across shifts and conditions

5 to 9

Annotation

Guidelines written, pilot batch reviewed, full annotation with QA pass

8 to 11

Model development

Transfer learning from a pre-trained detector, augmentation, iteration to target

11 to 13

Edge optimisation

Quantisation, hardware benchmarking, latency tuning

13 to 15

Line integration

PLC signalling, reject mechanism, operator display, offline buffering

15 to 17

Shadow mode trial

Runs alongside human inspectors, disagreements reviewed, thresholds tuned

17 to 18

Production cutover

Go-live, monitoring, operator training, retraining plan documented

Note the overlaps. Annotation begins before collection finishes. Model development starts on the first annotated batch. Sequential planning here would add five weeks.

The shadow mode phase is not optional. Two weeks running in parallel with human inspection is what makes the difference between a system operators trust and one they switch off.

Example 3: Enterprise demand forecasting platform (9 months)

A multi-region distributor wants SKU-level demand forecasts feeding procurement across 40 warehouses.

Months

Focus

Deliverables

1

Discovery and governance

Scope, success metric, data governance approvals, model risk framework

2 to 3

Data engineering

Pipelines from three ERPs, historical reconciliation, external data, feature store

3 to 4

Baseline and POC

Statistical baseline established, three approaches compared, direction chosen

4 to 6

Model development

Hierarchical forecasting, backtesting across regions, seasonality and promotion handling

5 to 7

Integration

Procurement system integration, planner override workflow, scenario tooling

6 to 7

Evaluation

Backtesting against 24 months, regional slice analysis, planner review sessions

7 to 8

Pilot

Two regions live, forecast accuracy measured against existing process

8 to 9

Rollout

Phased regional rollout, retraining pipeline, monitoring, planner training

Why nine months rather than four: three source systems with inconsistent product hierarchies, 40 sites with different operating patterns, a governance framework requiring independent validation, and a change management requirement because planners must trust the output enough to act on it.

The change management point is the one most often missed. A forecasting system that planners override every time has delivered nothing, regardless of its accuracy score.

Why AI projects slip and how to prevent it

Industry surveys consistently show a majority of AI projects run over schedule, and a meaningful share never reach production at all. The causes repeat.

Data problems discovered in week six

The most common cause. Everyone agreed the data was adequate. Nobody looked closely. Then modelling begins and the team finds three years of history with a schema change in the middle, a critical field populated only 40 percent of the time, or labels that turn out to have been assigned by a rule rather than a human.

Prevention: a formal data audit during discovery, with the ML engineer who will actually build the model looking at the actual data, not a schema description. Two days of work that routinely saves four weeks.

No agreed definition of done

Without a numeric target the project cannot end. Every review produces “can it be a bit better”, and it can always be a bit better.

Prevention: write the acceptance metric, threshold, and evaluation dataset into the statement of work. If the metric is met, the phase is complete. Improvements go into a subsequent phase with their own budget.

Scope creep during evaluation

Stakeholders see working output for the first time and generate new requirements. This is natural and it is not a failure of the stakeholders. It is a failure of process if there is no route for those ideas other than the current sprint.

Prevention: demo early and often so first contact happens in week three rather than week twelve. Maintain a visible backlog for phase two so new ideas have a home.

Integration surprises

The API is undocumented. The rate limit is 100 requests per hour. The security team blocks outbound calls. Production data has fields staging never had.

Prevention: validate every integration point with a live test call during discovery, even a trivial one. Ten integration smoke tests in week one prevents most of this category.

Confusing a demo with a system

A model that works on curated examples in a notebook is perhaps 30 percent of the work. The remaining 70 percent is everything that makes it survive contact with real traffic, real edge cases, and real users doing unexpected things.

Prevention: name the finish line explicitly at the start using the POC, pilot, MVP, production framework, and communicate the effort split so nobody believes the project is nearly done when the demo works.

The last mile of accuracy

The team hits 91 percent against a 95 percent target and spends six weeks trying to close a gap that the available data may not support closing.

Prevention: set the threshold based on business viability, not aspiration, and design the fallback path from the start. Systems that route uncertain cases to a human are more robust and ship far sooner than systems that must be right every time.

Silent degradation after launch

Not a delay in delivery but a delay in value. The model launches, performs well, and quietly decays as the world changes. Six months later someone notices.

Prevention: ship monitoring with the first release. Drift detection, performance tracking on a labelled sample, and an alert threshold that triggers retraining.

How timeline relates to cost

Timeline and cost are related but not proportional, because team size varies across phases and because some duration is waiting rather than working.

Duration

Typical team

Indicative cost range

Typical project shape

4 to 8 weeks

2 to 3

$12,000 to $35,000

API-based assistant, single integration

8 to 14 weeks

3 to 5

$30,000 to $80,000

RAG platform, document processing

14 to 24 weeks

4 to 7

$70,000 to $180,000

Custom ML model, vision system, agentic automation

6 to 12 months

8 to 15

$180,000 to $600,000+

Enterprise platform, multi-model, regulated

Ranges reflect blended global delivery rates and vary substantially by region and vendor model.

Three things worth understanding about the relationship:

Compressing a timeline usually raises cost. Delivering a 16-week project in 11 weeks means more people working in parallel, more coordination overhead, and often more rework. Expect a 20 to 40 percent premium for meaningful compression.

Extending a timeline does not lower cost proportionally. A project stretched from four months to seven because of slow decisions still consumes the same engineering effort plus additional coordination and context-switching cost.

Running cost is a separate line. Inference, hosting, vector storage, and monitoring are ongoing. For high-volume API-based systems, twelve months of inference cost can exceed the original build cost. Model this before choosing an architecture, not after.

How to compress an AI development timeline safely

Some compression is legitimate engineering. Some is deferred failure. The distinction matters.

Compression that works

Start with a pre-built foundation. Using proven accelerators for ingestion, retrieval, evaluation harnesses, and MLOps scaffolding removes four to six weeks of undifferentiated work. This is the largest single legitimate saving available.

Run discovery in parallel with data access requests. Access approvals are calendar time, not effort time. Starting them in week one instead of week four is free.

Use transfer learning aggressively. Fine-tuning a pre-trained vision or language model needs a fraction of the data and training time of a model built from scratch, and for most business tasks it performs better.

Build the evaluation harness before the model. Counterintuitive but reliably faster. It converts every experiment from a subjective discussion into a measured comparison.

Phase the release. Ship the highest-value 30 percent of scope first, then iterate. Real user feedback on a narrow release is worth more than a broad release built on assumptions.

Overlap workstreams deliberately. Integration scaffolding, interface work, and infrastructure provisioning can all proceed while modelling iterates, provided the interface contract is agreed early.

Reduce the decision loop. One empowered decision maker with a 24-hour feedback commitment can save more calendar time than any technical optimisation.

Compression that backfires

Cutting evaluation. The fastest way to a launch date and the fastest way to a production incident. Evaluation is where you find the subgroup where the model fails badly.

Skipping the data audit. Saves two days, costs weeks.

Adding people to a late project. Onboarding cost lands exactly when the team can least afford it.

Deferring monitoring to phase two. Without it you cannot tell whether the system is working, which means you cannot tell whether the compression was safe.

Reducing scope by removing error handling. Removing a feature is legitimate scope reduction. Removing the handling of cases where the model is wrong is not scope reduction, it is a defect.

The timeline after launch

AI systems are not delivered once. They are operated. Any timeline that ends at go-live is describing half the commitment.

The first 30 days

Elevated attention. Real traffic reveals input distributions no test set anticipated. Expect threshold tuning, prompt adjustments, and a handful of edge case fixes. Budget 20 to 30 percent of one engineer’s time.

Ongoing monitoring cadence

Weekly review of accuracy on a sampled labelled set, latency, cost per request, and error rates. Monthly review of drift indicators and user feedback themes. Quarterly review of whether the business metric is still moving.

Retraining cycles

Frequency depends on how fast the underlying world changes. Fraud and recommendation models may need monthly or continuous retraining. Document extraction models may hold for a year. Demand forecasting typically retrains monthly or quarterly.

Each retraining cycle on an established pipeline is days, not weeks, provided the pipeline was built properly during the original project. This is the return on the MLOps investment.

Annual maintenance effort

A reasonable planning figure is 15 to 25 percent of the original build effort per year, covering retraining, monitoring, dependency updates, model version migrations when providers deprecate versions, and incremental improvements.

For API-based systems, add the reality that providers deprecate model versions on their own schedule. Migrating to a new version requires re-running the evaluation suite and sometimes re-tuning prompts, typically one to two weeks of work each time.

Frequently asked questions

How long does it take to build an AI application?

Most AI applications take 6 weeks to 12 months. An assistant built on an existing model API ships in 6 to 10 weeks. A custom machine learning model takes 3 to 5 months. Enterprise platforms with multiple models and regulatory requirements take 6 to 12 months.

What is the fastest an AI project can realistically be delivered?

Around 3 to 4 weeks, for a narrow, well-defined feature built on a hosted model API with a single integration point, clean data, and an empowered decision maker. Anything faster is a prototype rather than a production system.

Which phase takes the longest in AI development?

Data acquisition and preparation, consuming 25 to 40 percent of the calendar on custom machine learning projects. On retrieval-based projects, document ingestion and retrieval tuning occupy the equivalent position.

Why do AI projects take longer than traditional software projects?

Because outcomes are probabilistic rather than deterministic. Traditional software either meets a specification or does not. An AI system produces a quality level that must be measured, and reaching a target quality level requires an iteration loop with an uncertain number of cycles. Data preparation and evaluation are additional phases with no direct equivalent in conventional development.

Does using an existing model like Claude or GPT shorten the timeline?

Substantially. It removes model training, training data collection, and inference infrastructure, typically cutting 60 to 70 percent from a comparable custom-model timeline. The tradeoffs are per-token running cost, provider dependency, and less control over model behaviour.

How long does a proof of concept take?

Two to six weeks. A POC should answer a single feasibility question on a data sample with no production infrastructure. If it is taking longer, the scope has expanded beyond what a POC should cover.

How much time should be budgeted for data preparation?

Between 25 and 40 percent of the project calendar for custom machine learning work. If a proposal allocates less than 20 percent, ask what assumptions it is making about your data.

Can an AI project timeline be compressed by adding developers?

Partially. Data annotation and independent integration workstreams parallelise well. Architecture decisions, evaluation design, and model debugging do not. Adding people after the midpoint of a project usually slows it down.

How long does AI model training take?

The training run itself often takes hours to days. The calendar time goes into the iteration loop of training, evaluating, diagnosing and adjusting, which typically spans 3 to 10 weeks depending on how far the first attempt is from the target.

Does compliance affect the AI development timeline?

Yes, materially. HIPAA-aligned work typically adds 3 to 6 weeks. GDPR and DPDP Act requirements add 2 to 4 weeks. EU AI Act high-risk classification can add 4 to 8 weeks for a first-time build. Running compliance work in parallel from week one avoids most of the delay.

What happens after an AI system launches?

Monitoring, drift detection, retraining, and iteration. Plan for 15 to 25 percent of the original build effort annually, plus concentrated attention during the first 30 days when real traffic surfaces cases the test set did not.

How do I know if a quoted timeline is realistic?

Check four things. Does it name a specific finish line, POC or pilot or MVP or production? Does it allocate meaningful time to data preparation? Does it include evaluation and monitoring as distinct phases? Does it state its assumptions about your data condition and integration surface? A quote missing any of these is not comparable to one that includes them.

Should we start with a POC or go straight to production?

If the technical feasibility is genuinely uncertain, start with a POC, because a fast no saves a great deal. If the pattern is well understood and proven elsewhere, going straight to an MVP is faster and cheaper than proving something already known.

How long does it take to fine-tune a large language model?

Ten to twenty weeks end to end. The training itself is short. The time goes into curating and reviewing the instruction dataset with domain experts, designing evaluation, and building inference infrastructure if the model is self-hosted.

What is the most common reason AI projects run late?

Data problems found after modelling begins. It is preventable with a two-day data audit during discovery, conducted by the engineer who will build the model, on the actual data.

Planning your own AI timeline

If you take one thing from this guide, make it this: the length of an AI project is decided by data readiness, integration surface, and decision speed far more than by model sophistication. Those three variables are all knowable before a line of code is written, which means a realistic timeline is available to you in week one if you are willing to look.

Before you commit to a date, run the checks. Audit the actual data. Confirm every integration point with a live call. Write down the accuracy threshold and the evaluation set. Name the finish line. Nominate the decision maker. Each of these takes hours and each removes weeks of risk.

Aalpha has delivered AI and machine learning systems for clients across the US, UK, Gulf, Africa and Asia since 2008, spanning retrieval assistants, computer vision, document intelligence and predictive platforms. If you want a timeline built around your specific data condition and integration landscape rather than a generic range, get in touch and we will walk through it with you.