How much more effort does it take to go from 90% proficiency to 91%?
Attention, focus, and energy are all finite resources. We have to spend them wisely and decide which goals are worth pursuing.
But, on the other hand, Olympic Athletes spend 4 years making small, incremental improvements for that extra 1%.
By saying yes to some things, we have to say no to others. Every job worth doing is sometimes worth doing well. Which ones worth doing is up to you.