“What is the one thing I can do that would make everything else easier or unnecessary”

This question is from the excellent Tim Ferriss podcast with Gary Keller

In the podcast Gary has this question “What is the one thing I can do that would make everything else easier or unnecessary” that he uses in business and his personal life. This question also forms the basis of his book

I believe that this insightful question can be used in project management in the following way –

What is the one thing that I as the Project Manager can do that would make everything in this project or project phase easier or unnecessary?