You build a product for yourself because it solves your problem. But then you try to see if it also solves other people’s problems. So you start with a few – your minimum viable audience (MVA).
You get to work with this small group and you get a sense if there is a market for your product. You get feedback and improve. And if the product does really solve the MVA’s problems, then you have true fans.
You just need 1,000 true fans to be comfortable in life.