Building and growing a business often require that a person be able to go without making any money for a quite a while, so by definition, these people are rare.

Building and growing a business often require that a person be able to go without making any money for a quite a while, so by definition, these people are rare. I don't think people with the talent to grow a business are that rare, but people with the talent and a conducive life situation are. And actually, even building a technically mundane product is quite hard, but more for the same reasons building a business is. It's a prototype that's easy to build, but buckling down to cross all the t's and dot the i's, and perform the boring work to make it a real product takes perseverance.