This was the best take-away for me:

   I also learned that my best tactic was to reconceive my bewilderment as curiosity, 
   and give free rein to it. I asked a lot of “why” and “what if” questions, 
   forsaking the “what” and “how” questions on which most senior leaders focus. 
   [...]
   My beginner’s mind helped us see our blind spots a little better, as it 
   was free of expert habits. We think of “why” and “what if” as little kid 
   questions, but they don’t have to be.