In a recent blog posting, Seth Godin said "If you’re not uncomfortable in your work as a leader, it’s almost certain you’re not reaching your potential as a leader." I think that sentence rings true these days. I have always believed that the best way to learn and to improve it to take yourself out of your comfort zone. That way, you are forced to deal with the discomfort of an unfamiliar situation and learn how to handle it. The more uncomfortable situations you put yourself in, the more you will learn and grow. This can apply to leadership or any other type of growth.
Sounds pretty simple doesn't it? Try it and see. Put yourself in an uncomfortable situation and see how good you feel after you have dealt with the situation successfully, or at least showed how you can push your limits even further.