> I don't want to make a little money every day, I want to make a fuckton of money all at once
- Russ Hanneman
The thing that distinguishes a startup from a small business is that the goal is growth - not being "great and stable." That said, I've worked at startups for years and I would not agree that good startups are "ego driven." They may seem that way on the outside if you take LinkedIn posts at face value or only read blog posts by people trying to hack it through publicity. They often have more understanding of the business reality of the markets they're trying to enter (or create) than anyone else, the value they add is by saying "fuck that" to a particular set of assumptions everyone else in the market might live by.
Sometimes that set of assumptions can't be discarded, but if it can and the startup is right, the backers stand to make a fuckton of money all at once.
Most startups fail, and most startups are run by founders driven by ego and vision rather than by disciplined market research or curiosity or understanding of the market.
The successful ones will either have gotten very lucky, or know lots about the market as you say. In fact the first main success hurdle is to understand the market well enough to know it's actually a market, and that it can be monetized.
All that to say, I agree with both you and OP.