Comment by Rendello
This reminds me of an article I read [1] where a surgeon, deciding his skills had room for improvement and lives could be bettered by honing those skills, had a retired surgeon come in occasionally and coach him. The external perspective and quick feedback improved his confidence and outcomes, and he convincingly advocated that practice.
That's also by Gawande! (And a great article, too.)
If you liked that, here's my own recommendation for something he's written: https://www.newyorker.com/magazine/2010/08/02/letting-go-2