First take a look at yourself.

Your leadership, if it is not continually growing, can be a lid to the potential of your people. Why? Because you teach what you know, but you reproduce what you are. You can't give people what you do not have. If you want to increase the potential of your team, you need to keep growing yourself.
Though the results are not always that dramatic, it is always true that followers become like their leaders. They are influenced by their leaders' values. They adopt their working methods. They even emulate many of their quirks and habits. That's why we must always be aware of our own conduct before criticizing the people who work for us. If you don't like what your people are doing, first take a look at yourself.