Your claim that most people who hit success dont have product vision may be true. Even though this might not be quantifiable, I get a similar idea from what I read. But I definitely think that it is not as uncommon as you think among Fortune 500 companies. I would think Bill gates( controversies/ethical questions apart) had a great vision. The reason why I say this is, I could say cancel a trip to Bahamas hoping to build something and see if I make it big. However, I would probably not drop out of a prestigious school to build something unless I am dead sure it will be a success. Obviously I am talking about Bill here.