Hard-Won Lessons in Investing | Petri Lehmuskoski | Neuvottelija 407

Summary

Petri Lehmuskoski, founder of Gorilla Capital, returns to discuss his book More Scars Than Trophies. Its central claim is that product market fit is an unusable term: it has never been defined, so it cannot be measured, and “we’re close to product market fit” tells an investor nothing — the early end and the late end of the concept are different worlds.

In its place the book offers four proof stacks. The last two, the scaling gate and the exit gate, resemble conventional thinking. The first two are where the book departs from it.

Buyer proof requires somebody to commit money, resources or significant time — a measurable commitment, not “I’m interested”, which is only an opinion. The term is deliberately buyer rather than user proof, because a user makes no economic decision: however enthusiastic they are, if no money moves through them it proves nothing. Miettinen’s contribution is the purchase funnel as theatre — free consulting in which an enthusiastic salesperson talks to an enthusiastic non-decision-maker — and Lehmuskoski’s addition is temporal: a startup has limited time, and time spent on theatre is time not spent trading.

Value proof is the original move, because it looks both ways. Value counts only after the customer’s own cost has been subtracted: training, switching systems, investment, or at worst the reputational cost to whoever signs, who can lose their standing over the decision. This is what explains large system failures — nobody worked out what costs arise on the side — and it is what tells you whether you can raise the price or are already too expensive. His extreme example is an ERP migration from Dynamics to SAP: a heart transplant in flight.

Hull speed runs through the conversation. A displacement hull has a mathematical top speed; fit whatever engine you like and the water flies, the stern drops and the fuel burns, but the speed does not rise. A company’s hull speed is the product of the entrepreneurs in it — the factors multiply rather than add — and pouring two or three million into a company whose proofs are not yet open is not merely wasteful but dangerous: you burn money going the wrong way for long enough that you then have to reverse. The classic version is hiring salespeople without evidence, three or four rounds of it, until you go and sell yourself and find the money gone.

Two measurement arguments are worth extracting. Revenue is a poor measure of value proof, because revenue arises without value proof: a tough founder or salesperson will generate it, but is it repeatable? And growth is not scaling — in growth inputs and outputs rise together, in scaling inputs fall while outputs rise.

The exit has to be built. The driftwood theory of exits is a bad theory, and Gorilla’s position is that the exit should be considered from the day the company is founded, because raising funding closes doors and options from the first round onwards. The counterweight is that building obsessively for one dream acquirer is dangerous — after the first contact they may simply not be interested — and Miettinen adds the AI-era curse of a counterparty taking the DD material and building the competing product.

On AI, Lehmuskoski makes three points. Evidence decays faster, because new tools keep invalidating what used to work. Bad evidence can be dressed up beautifully, decks having jumped a light year forward — he reports that decks now arrive with prompt-injection attempts aimed at whatever AI evaluates them. And the ability to build software with a team of coders is no longer a gate, now that a vibe coder produces an MVP over a weekend, which creates the odd risk that giving a customer too much value gives them an interest in replacing you.

What must not be outsourced is the search for buyer and value proof, because it starts from weak signals — the questions you did not know to ask — and a salesperson only asks what they know to ask. A customer drops a small signal about who really decides and whose budget is in play, and the salesperson lets it pass. This is also where Lehmuskoski places the human advantage: you can use AI for the measuring, but identifying and finding those proofs is still done better by a person, because what matters arrives as an aside.

The sharpest concrete example comes from Miettinen’s own field. An investment banker’s pain point is not the data room, the info memo, the teaser or their distribution — there is an endless supply of vendors offering those — but negotiating the agreement that produces a closing, during exclusivity. Lehmuskoski’s diagnosis: buyer proof may exist, but the value proof is very weak.

The episode closes on the camel and the unicorn. Comparing them is a little dangerous because they are not the same kind of thing: the camel is a way of getting somewhere, the unicorn is an outcome, and a camel can become a unicorn without going via the extreme. Gorilla’s third fund spreads across over 70 investment decisions, on the argument that picking the early winner has become harder than ever; the key measure at the investment stage is a realistic valuation, so a return is possible from an ordinary exit rather than only a unicorn one.

A note on the source

The MacWhisper transcript carries no speaker labels, but with a single guest the speakers are reliably distinguishable, and there are no gaps in the transcription. The book’s English terms (buyer proof, value proof, scaling proof, proof stack) appear in the transcript in numerous mangled forms and were normalised to the book’s own usage in the cleaned Finnish cue file. Spoken names that could not be verified were not guessed and are not repeated here.

Watch

The recording lives on the Neuvottelija channel: Karvaat opit sijoittamisesta | Petri Lehmuskoski | Neuvottelija 407. A Finnish edition of this episode is published at www.neuvottelija.fi.