I often times feel unsettled when not working -- even when I rationally know that working more at that time isn't necessarily productive, efficient or sustainable. That's probably not the most optimal attitude.

Also, I've debated it a lot, and at this point am not convinced that working all the time == success, having seen many examples both ways. Consequently I find it pretty hard to justify telling people to work all the time now (in order to achieve success), and in order to justify however much I'm working I just say that I think it is the moral thing to do.