I was also going to mention that confidence is a powerful predicter/cause of success & promotion, more so than any skills behind that confidence. Anecdotally, I've noticed people are much more successful in work & personal life when they are confident, as other people use that confidence as a shortcut for assessing actual talent & skills. Narcissism is a mix of unwavering confidence and self-assuredness that exploits this shortcut and lets people progress in life without any test of their actual abilities.