A team with one star is fragile. A team with a deep bench is dangerous.

Everything organised around one person has a single point of failure, and it will find it: an injury, a bad night, a person who leaves. A group with depth absorbs that, and it raises the floor too, because the fifth-best person being decent changes what you can attempt. Star systems feel strong and are brittle. Depth feels slow and is not.

Look at what your group would do if the best person disappeared for two weeks. If the answer is nothing, spend some of your time this month on somebody in the middle. Teach them the thing only one person currently knows.