The Dichotomy of Leadership by Jocko Willink, Leif Babin
The foremost requirement for potent leadership is humility, so that leaders can fully understand and appreciate their own shortfalls.
After many a vicious gunfight in Ramadi, "stand by to get some" was a running joke that eased the tension right when we knew trouble was coming. The more nonchalantly it could be said under the direst of circumstances, the funnier it was.