My body really, really wanted to reproduce when I was 15. It took a lot of civilization, socialization, willpower and some emulsion polymerization technology for me not to reproduce at 15.
You give anybody a billion dollars, and of course they are passionate. Passion is one of those things like willpower in that there's 'magical thinking' about it. You've got to be careful about 'magical thinking.'
The life of the professional writer - like that of any freelance, whether she be a plumber or a podiatrist - is predicated on willpower. Without it there simply wouldn't be any remuneration, period.