Although I teach courses on various topics related to leadership, I’m quick to admit it: Learning a lot about leadership won’t necessarily make you a great leader. 

Similarly, just because someone has 20 years of experience doing something doesn’t necessarily make him or her an expert. It’s quite possible—and common—for people to have the same experience, 20 years in a row. 

What oftentimes elevates truly great leaders above the rest is their tenacity, their commitment to never give up—and to never stop learning. It’s their ability to persevere through adversity with an open mind, applying the lessons they acquire along the way. 

One such leader whom I’ve always enjoyed listening to and reading about is United States Marine Corps General James Mattis (ret.). Among recent military leaders, Mattis is a legend, particularly if you talk with other U.S. Marines. 

Stories about his selfless, direct style of leadership abound. 

Additionally,