Work-Life balance - for God's sake - is NOT about constantly interrupting your work with "life" (sadly means only non-work activities for many...) or vice versa. On the contrary, it is about focusing on one thing at a time and therefore doing it - whatever you are doing - well.
So, when I'm at work, I want to minimize personal phone calls, emails and tasks and when I am home, I want to relax and think about personal things rather than attend an official phone call. Sometimes, when I'm enormously excited about an idea or a presentation or a project, I may tend to work on it during the weekend etc but then you can't let creative moments slip by and moreover who said only non-work activities constitute life? Similarly, if there is a personal emergency that needs to be catered to during work (office hours), then so be it. Exceptions are fine as long as they don't gradually get converted into something routine.