Because it is hard to trust those you hand your money to and not get in the way by checking in too often. Also, not every passionate engineer should be trusted that much. Being able to spot those that are passionate about what you want done, while simultaneously being both competent and trustworthy is a skill that will make you very wealthy, and almost no one has it consistently. A success or three may show that he is one of those people. Or that he is survivorship bias waiting for a reality check. I don't know how to tell, or I would be quite wealthy as well.