Willingness to receive feedback and be vulnerable in order to change for the better of the team.
The ability to take a loss and turn it into fuel to succeed.
Emotional intelligence - reading people, knowing how/when to give feedback or criticism.
Motivation to always be better.
Adaptability. Going from winning to losing during a game.... what is the game plan? We have seconds to react. It'd be the same in the work place, whether it be new people, obstacles, or changes to a plan.
Preparation, preparation, preparation.