Denial is the brains way of protecting its ego. As in you wouldnt admit you were wrong if you would be subsequently humiliated as a result - which is sometimes the case. Regardless of whether someone actually gives them sht or they just feel humiliated without external stimulus. Negative reinforcement I guess. Maybe their parents were hard on them or they still have a chip on their shoulder from when their parents didnt pick them up from soccer practice, and so the kid had to stand in the rain for an hour, even though they told them like 9 times the day before that it ends at 7, not 8, but NOOOO they have to take my sister to fucking ballet!