Why should your criteria out-weight anyone else. Sure vaccines are extremely important and education is key but emotional impact is also huge. You don’t have to save billions of lives to change the world. Whats to say that a simple maid can’t show world changing love to an orphan and make that orphan feel special and better about the world. Now you might think that through accumulating wealth, one doesn’t change the world, but who said that in the first place? The innovators who make companies like Uber because instead of sitting around and criticizing what others think “changing the world” is, in their perspective they did!