And time is definitely money, or rather, money is time. If you already have an income stream that is more than enough for your chosen lifestyle, spending lots of time on something that might give you a tiny bit extra seems like a bad choice. Why not spend time with his family, travel, take up a hobby, or at least write an app that is just for fun. Or one that has some sort of chance of making it really really big. Obviously up to him, but still, hard to understand.