To develop into one of the greats of leadership and to become a better person. It's imperative to practice humility.
According to Unbridling Your Brilliance, at the heart of humility is a desire to serve and a dedication to helping others become great. Never confuse humility with weakness; as a matter of fact, it takes great strength of will and character to put the needs of others before your own. To admit your mistakes, to be vulnerable, transparent, and fallible in front of your team.
Humble leaders exhibit behaviors that lift their team's spirits, self-esteem, and confidence to achieve anything imaginable.
I once pitched canned oxygen on BBC's Dragons' Den. I know humility :)