Ego drives us to do extraordinary things. It makes people want to win; strive to be the best in their field or industry. But ego can also be the most destructive force imaginable. In Extreme Ownership, Jocko wrote: “Ego clouds and disrupts everything: the planning process, the ability to take good advice, and the ability to accept constructive criticism. It can even stifle someone’s sense of self-preservation.” When you can’t control your ego, it can become the greatest instrument of your own destruction.