On the other extreme, 24/7 operations have redundancy.

A friend of mine explained that being an Emergency Medicine physician is a great job for work life balance, despite the fact that he often has to work ridiculous shifts, because he never has to take any work home with him. An Emergency Room is a 24/7 operation, so whenever he’s at home, some other doctor is responsible for whatever happens. So he gets to relax and never think about work when he’s not at work and not on call.