They are never around in a crisis. They break promises and substitute alibis for performance. They show up late or not at all. They are confused and disorganized. Their lives are a maze of unfinished business.
Maturity is the ability to make a decision and stick with it, riding out the storms that follow.
This requires clear thinking, and the courage to stand by your position once you have taken it. Immature people spend a lifetime exploring possibilities and then doing nothing. Action requires courage. And courage means maturity. Maturity is the ability to harness your energies and do more than is expected.