Managers are evaluated by other members of the group, and especialy by higher ranck managers, to their [[able people|ability to "make things happen"]]. Because managers are promoted by their precived ability they may tend to show-off their abilities in extravagnat ways. It was shown that narcissists tend to become leaders and are perceived as leaders, by other members of the group<ref>[http://www.myweb.ttu.edu/kdemarre/pdfs/BGCHKD.2008.PSPB.pdf Brunell, Amy B., et al. "Leader emergence: The case of the narcissistic leader." Personality and Social Psychology Bulletin 34.12 (2008): 1663-1676.]‏</ref>.Narcissists are overconfident and less empathic then ordinary people. It was found by some research (that I couldn't find) that overconfident are more likely to get hired then less confident managers, and this causes the bias toward overconfident managers.Narcissits are percived as attractive and leaders at first sight<ref>[http://www.researchgate.net/publication/40869027_Why_are_narcissists_so_charming_at_first_sight_Decoding_the_narcissism-popularity_link_at_zero_acquaintance/file/79e4150c6ee09257cd.pdf Back, Mitja D., Stefan C. Schmukle, and Boris Egloff. "Why are narcissists so charming at first sight? Decoding the narcissism–popularity link at zero acquaintance." Journal of personality and social psychology 98.1 (2010): 132.‏]</ref>.