Introduction
“If AI does half the work, why am I paying the same price?”
Sooner or later, most buyers of professional services will ask some version of this question. Some already have. In 2025 KPMG International, the global body of one of the Big Four, pressed its own auditor, Grant Thornton, to pass on the savings from AI, reportedly threatening to find a new one if it did not. The fee for its 2025 audit fell by 14%.1
The pressure is building because the productivity gains are real. In a field experiment with 758 Boston Consulting Group consultants, those using GPT-4 on tasks within its capabilities completed 12.2% more tasks, worked 25.1% faster and produced higher-quality results.2
Analytics and data science work is exposed to the same shift. Much of the effort in a data science project goes into preparing data, writing code and building reports, which is where AI helps most.
AI is cutting the cost of delivering analytics work. Should the saving simply lower the price, or change how retailers buy?
The largest firms are already changing how they charge. McKinsey said in November 2025 that between a fifth and a quarter of its global fees now come from outcome-based pricing, where fees depend mostly on results rather than on project scope and hours.3 Buyers are moving too. In a survey of 150 senior buyers of consulting, time-and-materials and fixed-price contracts were falling out of favour and subscription models were on the rise.4 Yet much data science work is still bought the familiar way, as a defined project that ends with a handover to the client.
Three questions follow:
- When AI cuts the cost of delivering an analytics project, who should keep the saving?
- Is a lower price the best a retailer can expect, or does AI make a better way of buying possible?
- What would a retailer need in place to buy analytics work on different terms?
Who keeps the saving?
Take a hypothetical data science project that takes £25,000 of a consultancy’s labour. Priced at twice cost, it is sold for a fixed fee of £50,000. With AI-assisted delivery, the same work takes £10,000 of labour. What should the retailer now pay?
The first answer is to pass the saving on, and the fee falls to £20,000. The consultancy’s profit falls from £25,000 to £10,000. This is a bet on volume. A firm can use AI to undercut its competitors and win more projects, or the same clients more often, since a £20,000 project is an easier decision to make. However, to stand still, it must win two and a half times as many.
The second answer is to hold the price. The fee stays at £50,000 and the consultancy’s profit rises to £40,000. It can serve the same clients with fewer consultants, and either shrink its bench or move people into new kinds of work.
Now consider the same project billed by the hour instead. Passing the saving on then happens by default, since fewer hours mean a smaller bill. The only way to hold the price is not to use AI to cut the hours, which keeps profit at £25,000 and means the saving is never made.
A cheaper project is not the same as a better one.
The billing model changes the incentive. Under a fixed fee, AI raises the consultancy’s profit. Under hourly billing, using it to work faster cuts profit. Economists studying procurement have long found that contracts which reimburse a supplier’s costs give it little incentive to reduce them, and are seldom the best choice for the buyer.5 Billing by the hour works in a similar way. Under either model, the saving tends to reach the client when competition forces it out, or when the buyer insists, as KPMG did with its own auditor.
However the work is priced, both answers treat the question as how to divide a saving. Neither changes what the retailer is buying.
What the retailer pays for one project
Illustrative
Passing on the saving cuts the fee and the consultancy’s profit. Holding a fixed fee keeps the saving with the consultancy. Holding an hourly bill means leaving the project as it was before AI.
What a project really costs
For a retailer, the fee is rarely the largest risk in a data science project. Three others matter more, and AI does little to reduce them.
The value is hard to judge in advance. Economists call products whose quality is hard to judge until they have been bought and used “experience goods”.6 Most data science projects fit that description. A buyer has to decide whether a £50,000 project will return more than £50,000 largely on the strength of a proposal and a presentation. If it does not, the budget is gone and the executive who approved it has to answer for it.
The wider evidence is not reassuring. In a Gartner survey of 644 organisations in the US, UK and Germany, covering AI from rule-based systems to machine learning and generative AI, the barrier to adoption most often cited (by 49%) was the difficulty of estimating and demonstrating value. On average only 48% of AI projects made it into production.7 On US net margins of around 1.3% in grocery and 5.6% in general retail, money spent on a project that does not deliver is hard to win back.8
The fee is often the smallest part of what a retailer risks.
Handover moves the burden to the retailer. Once delivered, the model has to be run by people who did not build it. Those skills remain hard to find. In the UK government’s 2024 Employer Skills Survey, when employers could not fill a vacancy because applicants lacked the skills, the missing skills included complex analytical ones in half of cases and advanced or specialist IT skills in a quarter.9
Models age. A study testing four common model types on 32 datasets from four industries found that model quality degraded over time in 91% of the 128 combinations.10 Engineers at Google have warned that machine learning systems commonly carry large ongoing maintenance costs, partly because they depend on data and a world that keep changing.11 A model built on last year’s customers, prices and products drifts as they change, and someone has to keep refreshing it.
Under a fixed fee and handover, all three risks sit with the retailer.
What the retailer takes on at delivery
Illustrative
The quote covers only the build. Handover, the skills to run the model and the work of keeping it current all arrive after delivery. So does the answer to the question that matters most, which is whether the project was worth doing at all.
What about paying for results?
The most widely discussed alternative is outcome-based pricing, where some or all of the fee depends on measured results, such as lower costs or higher sales. It is gaining ground at the largest firms. McKinsey says it grew alongside the multi-year transformation work clients increasingly ask for, AI programmes among them, and that such contracts can still include a fixed element.3
Measured against the three risks above, it answers the first directly. If the fee depends on the result, the consultancy carries much of the risk that the work delivers nothing.
It does less for the other two. Unless the consultancy also runs what it builds, the retailer still has to take the model over, find the skills to operate it and keep it current. And once the measurement period ends, so does the consultancy’s stake in whether the model keeps working.
Paying for results works only if both sides can agree what the results were.
It also brings a problem of its own, which is attribution. Retail sales move with promotions, prices, weather, ranging and competitors, so isolating the effect of one model is hard and easy to dispute. A study of outsourced logistics services found that when the client’s inputs are hard to separate from the supplier’s, attribution becomes contested, providers grow wary of taking on performance risk and relationships suffer.12 Forrester reports a similar pattern in IT services. Outcome-based contracts without a reliable baseline tend to create disputes, and most providers add outcome-linked fees only where results can be measured well.13
For a £50,000 project, designing a measurement regime both sides trust could take up a large share of the fee. Outcome-based pricing is best suited to large programmes with a clear, measurable prize.
Did the model do that?
Illustrative change in a retailer’s annual sales, £ million
closure
Many things move sales at once. Under outcome-based pricing, the fee depends on the size of the model’s bar, which is also the hardest one to agree.
Build and run
Build and run takes a different approach. Instead of handing the model over at the end of the project, the consultancy that built it carries on running it. This is essentially the managed services model, long established in technology, where a provider runs systems or business processes for its client under a longer-term contract. Managed services made up about half of Accenture’s $69.7 billion revenue in fiscal 2025.14
In the example, the consultancy prices the build at or near cost, £10,000, and then charges a monthly fee of, say, £5,000. That fee pays for monitoring the model, refreshing it as data changes and making sure the business can use the results. The people who built the model keep it working, so there is no handover.
For the retailer, the decision changes shape. Instead of committing £50,000 on the strength of a proposal, it commits £10,000 and then decides each month whether the model is worth £5,000. “Will this be worth it?” becomes “Is this still worth it?”, a question that can be answered with evidence.
The retailer stops paying when the model stops paying its way.
The consultancy can come out ahead too, if the work is properly built and automated. If running the model takes £1,000 a month of effort, its revenue in the first year is £70,000 and its profit £48,000, against £25,000 on the original fixed fee before AI. But it earns that profit only while the retailer keeps paying.
Build and run also offers much of what outcome-based pricing promises, without the measurement problem. There is no need to agree what the model caused, because the retailer’s decision to keep paying is the measure of value.
Counting the internal cost of handover and running the model in-house, a year of build and run need not cost much more than a cheaper project the retailer runs itself. It puts far less at risk before the value is known.
Cumulative cost to the retailer
Illustrative. Includes the retailer’s own cost of handover and running the model in-house.
Stop paying and the cost stops rising.
Months after the project starts
Hold the price£96,000 after a year
Build and run£70,000 after a year
Pass on the saving£66,000 after a year
Range of in-house costs
Handover options assume £10,000 of internal time for handover and training and £3,000 a month to run the model in-house. The shaded band shows a range of £5,000 to £15,000 for handover and £1,500 to £5,000 a month to run it.
Making build and run work
Build and run moves much of the risk from the retailer to the consultancy, but it creates a new one in dependence on the provider. A monthly fee is an advantage only if the retailer can stop paying without losing what it has paid for. Five terms matter most.
Ownership. The retailer should own its data, the model and the code, with access throughout, so that stopping the service does not mean starting again.
Exit. A handover on exit, priced in advance, keeps the option to bring the work in-house or move to another provider.
Service. The fee should buy something specific, setting out how often the model is refreshed, how its accuracy is reported and how quickly problems are fixed.
A monthly fee is an advantage only if it is easy to stop paying.
Price. An agreed review point and a cap on increases stop the running fee creeping up once the model is embedded in the business.
Quality. Cheaper delivery depends on AI being used well, so the contract should set out how AI is used, how its output is checked and who signs it off.
Build and run will not suit every project. Where the value comes from a single piece of work rather than from keeping something running, a conventional project may still be the better fit.
Who carries the risk
| Fixed fee, hand over | Outcome-based | Build and run | |
|---|---|---|---|
| Is it worth it?value risk | Retailer: Fee is paid before anyone knows | Consultancy: Fee depends on measured results | Consultancy: Retailer can stop paying any month |
| Can we run it?skills risk | Retailer: Retailer must find the skills | Retailer: Usually still the retailer | Consultancy: The team that built it runs it |
| Does it keep working?model ageing | Retailer: Retailer has to refresh it | Shared: Consultancy, until the fees end | Consultancy: Consultancy keeps it current |
| Can we measure it?attribution | Low: Not needed | Shared: Both must agree what it caused | Low: Not needed, use is the test |
| Can we leave?lock-in | Low: Low, the retailer holds the model | Retailer: Tied in until results are measured | Retailer: Retailer depends on the provider |
| Carried by the retailer | Carried by the consultancyShared | Low |
Outcome-based pricing moves the value risk to the consultancy but adds a measurement problem and usually leaves the running of the model with the retailer. Build and run moves both the value and the running risks, leaving dependence on the provider as the main new risk, which the terms above are designed to manage.
Sources
- S. Foley. KPMG pressed its auditor to pass on AI cost savings. Financial Times, 6 February 2026, open-access copy via The Irish Times.
- F. Dell’Acqua, E. McFowland III, E. Mollick et al. Navigating the Jagged Technological Frontier: Field Experimental Evidence of the Effects of Artificial Intelligence on Knowledge Worker Productivity and Quality. Organization Science 37(2), 403–423, 2026. Earlier version: Harvard Business School working paper 24-013, September 2023.
- P. Thompson. AI is reshaping how McKinsey makes money. Business Insider, 17 November 2025, syndicated by Yahoo Finance.
- Source Global Research. Emerging Trends: Pricing: Expectations vs. Reality, January 2025.
- R. Preston McAfee, John McMillan. Bidding for Contracts: A Principal-Agent Analysis. RAND Journal of Economics 17(3), 326–338, 1986.
- Phillip Nelson. Information and Consumer Behavior. Journal of Political Economy 78(2), 311–329, March 1970.
- Gartner. Gartner Survey Finds Generative AI Is Now the Most Frequently Deployed AI Solution in Organizations. Press release, 7 May 2024.
- A. Damodaran, NYU Stern. Margins by sector (US), data as of January 2026.
- IFF Research for the Department for Education. Employer Skills Survey 2024: Full UK research report, November 2025 (updated June 2026).
- D. Vela, A. Sharp, R. Zhang, T. Nguyen, A. Hoang, O. S. Pianykh. Temporal quality degradation in AI models. Scientific Reports 12, 11654, 2022.
- D. Sculley et al. Hidden Technical Debt in Machine Learning Systems. Advances in Neural Information Processing Systems 28 (NIPS 2015), 2503–2511.
- K. Selviaridis. Who’s to blame or praise? Performance attribution challenges in outsourced service provision in supply chains. Supply Chain Management: An International Journal 21(5), 513–533, 2016.
- A. Sunil. Outcome-Based Pricing In IT Sustainability Services: What Buyers Need To Know. Forrester, 13 August 2026.
- Accenture plc. Annual Report on Form 10-K for the fiscal year ended August 31, 2025. US Securities and Exchange Commission, filed 10 October 2025.