Focus requires that "cutting off." To focus on something means we cut off our attention from other things. The bummer is that often it is good things that lose our focus.
Jim Collins once said, "Good is the enemy of great." And I believe that.
We have limited resources of time and energy. We can't invest them everywhere and we have to invest them wisely. Here's the thing: only you can choose the investment. Others in your life will have lots of ideas about what you should pursue, but that is a quick recipe for feeling like you aren't fulfilling your purpose. This doesn't make choosing a selfish endeavor. On the contrary, for each of us our higher purpose is in serving others, but we have to choose where that is, and I believe the biggest clue to our higher purpose is the thing that gives us joy.
Choosing means that sometimes we have to have a hard conversation. It also means we may disappoint those who have aspirations for us.
But to pursue the things that we were uniquely put on this Earth do do requires a continual pruning of our schedules, budgets, commitments, closets and loves.
Focus is what takes us from good to great, but it isn't effortless. Focus is a discipline.