The Myth of Product-Market Fit

Everyone talks about product-market fit like it’s a finish line. You build, you iterate, you hit PMF, and then you scale. Except that’s not how it works.

Product-market fit isn’t a binary state you achieve—it’s a gradient you climb. The question isn’t ‘do we have PMF?’ It’s ‘how strong is our PMF, and in which segment?’

Early retention is the only signal that matters. If 40% of your users come back the next day, you have something. If 5% come back, you don’t—no matter how good your engagement metrics look in that first session.

But here’s where most founders mess up: they look at overall retention instead of cohort-specific retention. Your first 100 users? They’re friends and early adopters who will stick around out of politeness. Your next 1,000? They’ll tell you the truth.

Stop asking if you have PMF. Start asking: which user segment has the strongest retention, and how do we find more of them?