Learning the difference between output and performance becomes a key factor in your ability to not only lead a company, but to drive it. A lot of times, people will focus more on the output aspect of the job and think that just because they are clearing a bunch of to-do tasks that there is nothing they need to worry about. However, this is not the case at all. What one ought to be more concerned about is the issue of performance. How we perform in a given task shapes and transforms us as a whole to continually be better leaders. Take a look at this key difference in this talk from Tony Robbins.
Watch:
https://www.youtube.com/watch?v=EyP2bjORL1Q