Several studies have concluded that a sense of psychological safety is an important component of a successful team. It could be roughly described as the leader creating an environment in which team members can feel confident to speak up or get the job done without fear of being turned against if they are wrong or punished if they are wrong. A sense of psychological safety allows us to openly and frankly question beliefs, opinions or even the way we do things.
If these issues are important to us, then it is worth learning to balance confidence and doubt. In my experience, a healthy amount of self-doubt can keep us from being arrogant assholes. Or as the ancient Japanese proverb goes: we are less annoying if we keep our mouths shut. 🙂