Specifically, working and living in another country would teach you to be less quick to assume that everyone thinks like you and that everyone understands your point of view.  This is valuable even when you are working in your own country.  We tend to think that everyone has the same points of view that we have and that other people will, therefore, agree with us.  If you live and work in another country, you get shorn of that notion to some extent.  If that happens, you become better at paying attention and finding out what other people think.  You also become better at making sure that you clearly express your thoughts and the assumptions that underlie them.  Thus, living in another country improves your ability to truly communicate with (both in listening and speaking) other people.  This ability can come in handy in your own country as well.