Psychological safety
The belief that speaking up will not be punished — the precondition for learning.
Psychological safety is the shared belief that one can raise a problem, admit a mistake or disagree without being punished or humiliated.
It is not comfort, and it is not the absence of pressure. High-performing teams often combine high standards with high safety; the combination is what allows problems to surface early.
Leaders build it primarily through their reaction to bad news. What happens in the first thirty seconds after someone reports a problem sets the norm for the next year.