Why does David Heinemeier Hansson (@DHH) still go to work now that he is a millionaire ?
Given that neither Jason (co-founder of Basecamp) nor David H. Hansson need to go to work, they should only continue because working brings them joy. DHH could start another company, or start another pursuit, but he chooses not to. Basecamp is a place that allows David to program and Jason to design, and that works for them, on their terms. Same goes for growing the company. If they were to try and get really big, eventually they would hit a point where they would not be able to do their favorite things, and that would not be enjoyable, so why do it?