It is not always about the money. After a certain point, where you are set for life in the lifestyle you want, then work may be the reward which is sought. Look at Bill Gates. He could burn a million dollars a day in his fireplace and never run out. He still works hard, but on things he thinks will change the world. In fact, he has signed up to give most of his money away to charity upon his death. Same for the Oracle of Omaha.