If they don't have customers you won't either.

Being passionate and interested in a problem doesn't mean there is a market for said problem. This doesn't mean that it's not valid to feel that way, but a viable business might be hard if not impossible to build in that niche. Maybe I'm passionate about and interested in ornamental gourd futures [0], doesn't mean it's a way to build a business.

[0] https://www.reddit.com/r/wallstreetbets/comments/kzoh1c/i_am...

Depends on your passion/interest.

This article is assume startup - you raise a lot of money and get a lot of people to help you build the product fast to get to the very large market. A valid strategy and can earn you a lot of money if there is a large market you can serve.

However there are a lot of markets that are not that big. If your passion is something Pet Rocks - that will probably be a tiny market (it was once big for a short time, but the time is over and unlikely to come back - thought maybe I'm wrong). You are unlikely to every grow a large business because there are so few other people interested in your passion.

There are other markets where your interest/passion will make one person a nice income, but can never scale to a large company. The investors this article is concerned about want nothing to do with it: they can never make their investment back. However you as a person can make a lot of money in this niche self funding the company and growing no faster. It will be hard work, and it will only get you into the lower end of the upper middle class, never rich - but that can be a nice life.

Or you can discover the hard way there is only so much you can take of your interest before you burn out.