Successful leaders know how to balance focus, discipline, and understanding in dealing with strategies and with people. They need to be good anticipators and thoroughly understand their team and its strengths and weaknesses. They need to be perseverant but not stubborn. Maybe most important, they need to know how to gain from a loss.
My biggest failures as a leader were probably being to be too averse to controversy, too unwilling to take the harder short-term road to reap the greater long-term success, and leaving failing subordinates in place too long.