This really resonates deeply for me as well. When I was completely buried with difficult projects, I would occasionally complain about being "too busy". However

This really resonates deeply for me as well. When I was completely buried with difficult projects, I would occasionally complain about being "too busy". However, when things normalized to 40-50 hours a week, I would feel lazy. I reached a point where building a reputation as being someone capable of delivering when the situations were not ideal was a far greater motivator than money or free-time. I found Daniel Pink's "Drive" an interesting read on the topic of what really motivates in the modern era.