If you have $20 million, you can put as much of your time (which you actually own) into your idea as you think it needs. Once you have proof of concept, you can look for funding and then hire people and have a burn rate. I don't think, however, people with $20 million are going to stake their whole fortune on one startup. That's just irresponsible, no matter how good the idea is.
Also, with that kind of money, you can actually socialize with VCs as equals and, if none of them want to fund you after a few years, it's probably because your idea sucks (as a business). Then you do not hire other people and you do not lose your $20 million.
That's what I would do. I wouldn't hire a single person (for cash, not equity) until I had the validation of knowing other people were willing to invest. This is because I know I'm smart, but I've done creative work (game design, writing) and know that half of even my ideas are bad. Creativity is just about having the persistence and judgement to develop the good ones.
Also, with that kind of money, you can actually socialize with VCs as equals and, if none of them want to fund you after a few years, it's probably because your idea sucks (as a business). Then you do not hire other people and you do not lose your $20 million.
That's what I would do. I wouldn't hire a single person (for cash, not equity) until I had the validation of knowing other people were willing to invest. This is because I know I'm smart, but I've done creative work (game design, writing) and know that half of even my ideas are bad. Creativity is just about having the persistence and judgement to develop the good ones.