Two weeks that turn “we are building X” into a written list of what has to be true, the cheapest test for each of those things, and a decision rule agreed before the data arrives. Where the fastest test is a working artefact, we build the artefact — a landing page, a clickable prototype, a thin slice that runs.
Generative AI has made building the cheapest thing a founder does. A prototype that needed a technical co-founder and three months now takes a week. That is a genuine gain, and it has an unpleasant side effect: building used to be expensive enough to force the conversation with customers, and it no longer forces anything. The result is teams with a working product, a long roadmap, and a customer list of three people who were being polite.
This engagement puts the expensive question back in front of the cheap one. We write down what has to be true for the business to work — demand, willingness to pay, reachability, the thing you are quietly assuming about how the customer currently solves this — and order them by what would kill the company fastest, not by what is easiest to check. Each assumption gets one test, one signal that counts as a pass, and a decision rule written down before the test runs, so a weak result cannot be reinterpreted as encouraging.
Then we run the tests we can run in the time, and where a test needs something built, we build it. That is the difference between this and a coaching engagement: the person designing the test is the person who can ship the landing page, wire the payment link, or cut a working slice of the product on the same day. Nothing waits for a developer who is not in the room.
The method here is not new. Customer development and the build–measure–learn cycle have been in print since 2011 and 2012 (Ries; Blank & Dorf). What changed is the cost of the build, which is exactly what makes the discipline harder to keep and more worth paying for. It is also the subject Risto is studying formally, in a study whose fieldwork has not happened yet and whose page says so.
The same question, asked where nobody is paying for the answer: the research behind this engagement.
The method is Lean Startup and customer development, and we say so rather than rebranding it. The reason it needs buying again is that the economics underneath it changed. When building took three months, the cost of the build enforced the discipline for you. Now that it takes a week, nothing does, and the teams skipping validation are not lazy — they are responding rationally to a build that no longer hurts.
Because most validation stalls on something needing to be built. A test that requires a landing page, a payment link, or a working slice of the product gets scheduled, then dropped. Being able to build the test on the day it is designed removes the usual reason validation does not happen, and it keeps the person who wrote the assumption honest about what the result actually showed.
That is a result, and it is the one worth the most. It arrives in two weeks rather than after eighteen months of building, and it usually arrives with a specific reason attached — wrong customer, right customer with a cheaper existing workaround, real need with no budget line to pay from. Two of those three are fixable without abandoning the idea.
Yes, for the mechanical parts: drafting test material, building the artefacts, sorting through what came back. Not for the judgement calls. An assumption register written by a model reads well and is missing the assumption you did not want to look at, which is the one that matters.
The research asks the same question in a setting where nobody is paying us to like the answer: how founders actually use AI across the innovation process, and whether their work moves into validation or past it. The method feeds the client work now. The findings cannot until they exist — the interviews run in late 2026. See the research page.
Scope note. This is product and business model validation, not market research at survey scale and not investment advice. Small-sample evidence tells you whether to keep going, not what your market is worth. We will say which of the two you are getting.