Call me naive, but I don't think Elon Musk is in it for the money. He's just having the time of his life, making his dreams come true and all that... I think his motivation is not so much wealth/profit, but more to innovate and make something new. I believe the world would benefit if there were more people like him out there...
I think this is exactly what drives him.
I am ashamed to admit if I had the money he had when 24, I would have retired to some exotic places or relentlessly travelling the world.
Hes instead running two of the most disruptive firm in the world working 80 hours week.