A deliberate deception (misleading one’s colleagues, or a patient, or a boss) has at least one clear benefit. The person doing the deceiving will, by definition, recognize the deceit and will inwardly acknowledge the failure. Perhaps he will amend the way he does his job to avoid such a failure in the future. Self-justification is more insidious. Lying to oneself destroys the very possibility of learning. How can one learn from failure if one has convinced oneself —through endlessly subtle means of self-justification, narrative manipulation, and the wider psychological arsenal of dissonance-reduction — that a failure didn’t actually occur?
Syed, Matthew. Black Box Thinking: Why Most People Never Learn from Their Mistakes—But Some Do. Portfolio, 2015.