I will add another fact, that american workers get less vacation than other workers in other countries. One aspect of why they work more that I haven’t seen above is that they want to make a good impression. People who want to move up the ranks will take it upon themselves to work harder and longer than their peers in order to get their work done on time and done well. People notice when you work long days. They will take that into account when deciding who should get a promotion, along with the work that you’ve done. Some people do have the passion and want to work more, some people are paid hourly and need the extra money, and others don’t want to be outshone by their peers. The main factor why I believe that people work that long is because they hope for upward mobility through the ranks and want to make a good impression, doing more the the expected norm. Whether or not that’s a good thing is another discussion.