The key difference is the founder built a product in search of a problem to solve, rather than the other way around.

The "secret" is just to talk to people in the field they're trying to "revolutionize," and ideally observe them work. Often, people become blind to workflow problems and workarounds become normal process. They never even consider to look for a better way to do something. Those are the opportunities for founders to solve.

But what I've seen a lot is founders just arbitrarily coming up with an idea that sounds cool on paper, raising money, and only realizing too late that there is zero actual market fit.