I have written here fairly often about research by Harvard Business School's Boris Groysberg on the virtues and limits of star employees. One of my posts described has delightful research that shows firms should steal superstar women, not men. It turns out that when star men move to another firm, they tend to do a lot worse in the new setting. In contrast, star women tend to sustain their performance when they go to another firm. Groysberg suggests this difference is explained because women are more skilled at establishing new relationships and less likely to engage in dysfunctional internal competition in their new firms.
Boris's new research is equally fascinating, a while back, he sent me an article he wrote with two colleagues called called "Too Many Cooks Spoil the Broth" (see complete reference below). They studied over 6000 industry analysts from 246 research departments in Wall Street firms — these are people who write reports about the current and expected performance of firms, and who specializes in particular industries. Their reports predict future earnings for companies and contain recommendations about whether to buy or sell stocks. As Boris and his colleagues show, some of these analysts are stars, selected by the Institutional Investor as being the top person in their industry and being picked as a star is worth hundreds of thousands of dollars in compensation. The results of this research are interesting because, while some leaders might think that there is no such thing as having too many stars, Boris and his colleagues found a curvilinear relationship between the number of stars in a group and overall performance — so, having a few stars help, have a few more doesn't hurt (but doesn't help), but groups reach a tipping point where too many stars seem to dampen performance.
Groysberg and his colleagues suggest that the "too many cooks" problem happens because partly because, when a group is filled with individual stars, the dynamics degenerate because people devote excessive attention to the the internal status game and competition and hesitate to share information that may help the group as a whole, but will threaten their standing in the group. In other words, when there are too many stars, people focus on what is best for themselves, see other top performers as people who are in the way rather than people they should help, and the overall performance of the team seems less important.
This is just one study, but a quite rigorous one one. And it adds for evidence to the claim that Jeff Pfeffer made in the The Knowing-Doing Gap that dysfunctional internal competition is one of the most vile impediments to turning knowledge into action in groups and organizations. Once the game becomes "I win when you lose," the team or organization suffers.
Here is the complete reference: Groysberg, Boris, Jeffrey T. Polzer, and Hillary Anger Elfenbein. "Too Many Cooks Spoil the Broth: How High Status Individuals Decrease Group Effectiveness." Organization Science (forthcoming).