It is good to make a mistake, especially in the face of one's peers. Gentle humiliation is enough to relieve the pressure of always being right in the face of one's peers and vice versa, and then lessons from one's mistakes can be shared throughout the group.
Masteries too should be balanced against one another. If one person becomes far more skilled than the others and then takes over, the rest working under that person begin to experience an atrophy of skill. Instead of putting thought into mastering one's domain, one is constantly taking cues from another person, and those higher-level skills suffer. One becomes a drone under another's lordship.
Again, mistakes remove this constant mimetic pressure, this competition towards mastery. One can make room for others to gain competency and thus autonomy over their immediate spheres.
