"Know yourself" includes knowing when you excel as a principal and when you excel as a lieutenant. Many entrepreneurs I know think of themselves as CEO material. Generic ambition points to the top. But not everyone is best suited for the top job all the time, even if they are sufficiently capable.
You are not either a principal or lieutenant. Teams and circumstances vary. Part of being a good team player is knowing your role within the team. Most of the time I find myself a principal / CEO, but there is at least one area where I excel and enjoy more a lieutenant role: basketball.
My sophomore year of high school and the spring league immediately thereafter was the peak of my basketball career. That year I started on the varsity team. I was a key contributor but a senior was the undisputed team leader. He was a talented player. Together, we worked well, and in a supporting role I consistently racked up 10-20 points a game. That spring I played in the Slam N Jam Development League in East Oakland. Our team consisted of a handful mid-major D1 college basketball prospects. I was probably the weakest on the team in terms of athleticism and skill, but I banged around down low, contributed 3-4 buckets each game, played good help defense, moved well without the ball, and helped communicate coach's instructions on-court. I was a solid role player on a thuggish team of athletic stars.
At most other points in my playing career I was the (or one of a couple) go-to guys. My final two years of high school ball I was a co-captain and more responsible for scoring and winning. Yet, I never felt I performed at my peak level, and our team results, despite one regional playoff birth, were mediocre. For example, I thrived offensively when I could get the ball well-positioned on the block for either a back-to-the-basket post move or a face-the-basket shot or spin. For this to work the guard with the rock needs to know how to pass and be well-spaced, the other post players need to be well-spaced, and everyone else needs to move to get open in the case of a double team. If all this happened and I had my shit together, I was effective. Otherwise, I wasn't good enough to make things happen on my own. On the defensive end, I was skilled at rotating and moving and orally coordinating a man-to-man help defense framework. This relies on the whole team moving in concert. But I was not capable of "shutting someone down" or playing intense in-your-face defense on their best player up and down the court. Finally, I didn't care enough about the sport to lead by example on the "killer instinct" front which is what "the guy" is supposed to do on a team.
By the way, this is just one example of a broader life lesson you can learn from playing sports….
Bottom Line: "Know yourself" includes knowing when you excel as a principal and when you excel as a lieutenant. Teams are most effective when each player knows his role.
(thanks to Andy McKenzie for his feedback)