Product-market fit
Why it matters
Nothing else makes up for its absence. Good marketing, a sharp sales process and tidy operations only delay the reckoning if there is no real pull, because none of them can substitute for it. Scaling before it exists means paying more to acquire customers who then leave.
It also changes what the next pound of effort should buy. Before fit, the job is learning: who the buyer is, what they will pay for and why they stay. After fit, the job is repeating what works. Hiring salespeople or raising ad spend in the first phase burns money on answers the company does not yet have. Skipping the second phase leaves demand unserved.
Fit is not permanent. A shift in the market, a new competitor or a change of target customer can weaken it, so the signals are worth rechecking each year.
What it is
Marc Andreessen popularised the phrase in 2007, describing it as being in a good market with a product that can satisfy that market. In practice it is visible as a change in behaviour. Before it, every sale needs convincing, and customers drift away. After it, prospects ask for the product, existing customers renew and some bring colleagues without being asked.
Say a founder tests a new service and sells through discovery calls. When prospects start booking a paid pilot without being chased, and a few bring a colleague along unprompted, the effort has shifted from convincing to being asked.
Common mistakes
- Mistaking friendly feedback for demand. Polite praise is not payment.
- Declaring fit after a handful of enthusiastic early users.
- Pouring money into acquisition before retention is visible.
How to test it
- Interview people who match the target customer before building further.
- Turn the riskiest assumption into the smallest paid test, such as a pre-order page, a manual pilot or a deposit.
- Set a numeric, time-boxed target for that test and read the result honestly.
- Track whether paying customers return, renew and refer others, not only whether they signed up.
- Try the survey method suggested by Sean Ellis. Ask users how they would feel if they could no longer use the product. If at least 40% say "very disappointed", that is taken as a sign of fit.
