Over the course of interviewing more than 100 world class leaders for my podcast,The Learning Leader Show, I’ve found that there are certain characteristics that appear to be evident in all of those who have sustained excellence over an extended period of time. What is excellence? The renowned author and social commentator Seth Godin describes excellence this way: “Excellence means that you’re indispensable. At least right now, in this moment, there’s no one else I would choose but you. You, the excellent one, are so surprising, so delightful, so over-the-top and, yes, so human that there really isn’t anyone else I’d rather dance with.”

Based on 100+ interviews with successful leaders from all walks of life, following are my top ten characteristics of leaders who sustain excellence:

1. Curiosity – Kat Cole, President of Focus Brands, lists curiosity as one of the four critical elements of success. Author Dan Pink said “Curiosity … Leaders follow their noses” as the first trait common among high performers. Whitney Johnson, author of “Disrupt Yourself,” lists curiosity as the key to growing from one learning curve to the next. Seth Godin boils down his massive success to his practice of “noticing things.” My website asks “Are you massively curious?”

2. Self-Awareness – The legendary entrepreneur Gary Vaynerchuk calls this the most important characteristic of great leaders. They very much know what they do best, and similarly they have a vivid sense of where they struggle. Self-awareness requires understanding each of those realities. It’s about betting on their strengths and understanding their short-comings. They double down on their strengths and, where it is important, make attempts to turn a liability into a strength. Famed mountain climber and inspirational speaker, Alison Levine, discussed why she wasn’t the best at lugging a 150 pound sled while skiing to both poles. She had to creatively find another way to bring value to the team. She was shorter than those who were on the expedition with her. While the taller, more muscular guys carried some of her weight when moving, she always made a point of digging out their snow shelters. She exclaimed, “I needed to find a way to turn my liability into a strength. My height (or lack thereof) hurt me while we were moving, but it helped me when digging out the snow shelters around our tents. That was my way to contribute to the team.”

3. Voracious Reader – Harry Truman once said: “Not all readers are leaders, but all leaders are readers.” Literally 100% of the great leaders I’ve spoken with are aggressive readers. They are constantly suggesting books, giving them away as gifts, and READING them. The great investor Charlie Munger (Warren Buffett’s business partner) explained, “In my whole life, I have known no wise people who didn’t read all the time – none, zero.”

4. They Take Time To Think and Focus on the Important – Best-Selling author Cal Newport calls this “Deep Work.” Deep work is the ability to focus without distraction on a cognitively demanding task. It’s a skill that allows you to quickly master complicated information and produce better results in less time. Deep work will make you better at what you do and provide the sense of true fulfillment that comes from craftsmanship. Dwight D. Eisenhower said “What is important is seldom urgent and what is urgent is seldom important.” Important tasks are things that contribute to our long-term mission, values, and goals. Sometimes important tasks are also urgent, but typically they’re not. Some examples of this: relationship building, writing thank you notes, journaling, reading, meditation.

5. Confident – “Do or do not. There is no Try.” Seth Godin reminds us to understand that “The Dip” will be there. The Dip is the path from initial launch enthusiasm through doubt and second guessing to long term success… It will be there. The greatest leaders are confident and determined. They know they will make it through the tough times no matter what. When failure hits, as it inevitably does from time to time, they take time to understand why and then move on. They would tell you to ignore the people who say it can’t be done. I personally don’t see those people as any sense of motivation. I’m motivated by the people who believe in me. I’m motivated by my wife, my children, my brothers, my parents, and close friends. They motivate me because they believe in me. They know I’m going to do something great. I work hard to prove them right.

6. Overwhelming Sense of Optimism – This goes hand in hand with confidence. The best leaders simply believe that great things will happen. I learned this from a young age watching my Dad. To this day, he’s always the most optimistic person in the room. He acts as if every day is Christmas. To him, that is his duty as a leader (He also happens to lead a 950+ sales force that covers all of North America). He believes it so much that it becomes true. Great leaders have a sense of “Pronoia.” Pronoia means that you truly believe the world is out to help you. There are a lot of under-performing people who feel the opposite. They will say things like, “With my luck, this will go bad.” In my case my wife and I focus on this phrase: “With our luck, we’re going to absolutely crush this task…” Are we always correct? Of course not, but that doesn’t mean we don’t believe it. We know this mindset has helped us achieve levels of success.

7. Always Trying to Level Up – My friend Joey Coleman spent $75K to be part of Tony Robbins Platinum Partners group in order to raise the level of his peer group. He had a fine set of friends, but they weren’t leveling him up. So he invested in himself in order to be surrounded by greatness. The investment paid off (He now gives world class keynote speeches all over the world charging $20,000+ per speech). All of us should heed the concept of choosing ones closest friends carefully. Entrepreneur/Author Jim Rohn said, “You are the average of the five people you spend the most time with.” The best leaders think critically about the people they decide to spend time with… If they aren’t helping them level up, then they find people who will. This doesn’t mean they completely rid themselves of all of their current friends. Rather, they spend less time with them than they do with the people who raise their level.

8. Constantly Helping Others – The best leaders look for opportunities to be of service to others. Great leaders love being mentors. They love helping others. As my friend Aaron Campbell explained to me one day, “Great leaders are mentors, teachers to their core. They never disparage others; to them everybody is a student – especially those who disagree. They have a searing intellect, always questioning – they understand that precedent’s only proof is that it came first.” I’ve experienced this so many times and typically it’s from the people who most would assume are extremely “busy.” They make introductions, talk via Skype, and provide incredible advice on how to continually improve as a leader.

9. Humility – They carry an attitude of empathy thinking of the needs of others first. They are not concerned with who is “right or wrong”. They take time to self-reflect realizing that the world is largely a level playing field and the way we behave largely guides our long-term success. The greatest leaders in the world treat the janitor with as much respect and value as the CEO. Rob Nielsen, coauthor of Leading with Humility, explains “When people are demonstrating these behaviors—self-awareness, perspective, openness to feedback and ideas, and appreciation of others—employees happier in their work and they perform at a higher level.”

10. Morning Routine – I’ve spoken with over 100 world class leaders on my podcast, The Learning Leader Show… All of them have a morning routine. Typically it starts very early and involves some of the following: Drinking a lot of water, writing, reading, listening to podcasts, meditating, moving their body (working out). They take control of the day by planning their morning routine. If they have kids, this is the best time of the day for leaders to have to themselves. Sit, think, write, read, breathe, move your body. This personally has had as big of an effect on me as any practice I’ve implemented.