One of my favourite interview questions is ‘What do you do outside of work?’ Personally, I believe that a well balanced lifestyle (i.e. Having a life outside of work) leads to a healthier view, better productivity and a healthier team.
I was speaking with a friend a while back and he mentioned how his boss does not have kids, does not have hobbies and the only thing that he does is work. That lifestyle falls upon his reports in the form of non-stop emails, little respect for personal time, no ability to connect beyond work items (What do you talk about?) and an attitude which burns people out (and makes them hate working for him).
He wished his manager had a hobby.