By Laura Entis, Entrepreneur.com

When hiring employees, conventional wisdom dictates that one should always try and select the superstars, those men and women who excel at their job so thoroughly they put the average human to shame. After all, the assumption that a corporate team packed with ten peak performers will outperform a unit that consists of five excellent achievers and five merely good ones seems like a safe bet.

But while top-tier talent is clearly a must-have for any business, a recent study published in Psychological Science adds a shade of nuance to the talent equation by suggesting that when it comes to team performance, there may be a talent-saturation point.

In a series of experiments, researchers at Columbia University and other institutions picked apart the relationship between talent and team performance in sports by examining professional athletes playing in the National Basketball League, Premier League and Major League Baseball. To identify elite players, the researchers used a set of criteria in each league – in the NBA, for example, players were ranked via their Estimated Wins Added, a statistic used to approximate the number of victories a player adds to a team’s season total above what a ‘replacement player’ would produce, along with whether or not they were selected for the league’s annual All-Star tournament. Meanwhile, in the Premier League, elite players were chosen by cross-referencing national teams with powerhouse club teams, such as Real Madrid and Chelsea; those who appeared on both lists were considered superstar talent.

For all three sports, the researchers calculated the percentage of ‘elite’ players’ on each team, and then compared that number to the team’s overall performance (measured by its win-loss record).

The results varied by sport. In baseball, the more talent the better: Team performance continued to improve as the percentage of elite players on a team climbed.

But in basketball and soccer, this steady upward trend didn’t hold – instead, the researchers found that while the addition of talent was initially beneficial to a team’s performance, there was a saturation point. Once a team’s ratio of elite players to non-elite ones surpassed approximately 2:1, returns began to diminish. Not only that, but basketball and soccer teams with the highest percentage of top athletes had, on average, worse win-loss records than teams with a more mixed roster.

The study’s authors chalk this difference up to the inherent difference in baseball’s style of play versus soccer and basketball’s: “Prior research suggests that baseball involves much less task interdependence among team members, compared with football and basketball,” they wrote.

In other words, basketball and soccer are quintessential team sports, where success depends on players’ ability to work as a cohesive unit, while baseball is more about individual performances.

“Our findings reflect the disappointing fact that teams of superstars often fail to live up to expectations,” the authors explain. They’re talking about sports teams, but their finding can be extrapolated to include any unit that needs to function as a well-integrated whole. Or, as the researchers explain it:

“Just as a colony of high performance chickens competing for dominance suffers decrements in overall egg production and increases in bird mortality, teams with too much talent appear to divert attention away from coordination as team members peck at each other in their attempts to establish intragroup standing.”

In other words, too many top-tier employees can cause a team’s performance to suffer as high-performance individuals jockey for position within the group. Instead, the authors advise, team-builders should consider pairing high-flying over-achievers with a solid percentage of competent, if not exceptional, workers.

“In many cases, too much talent can be the seed of failure,” the study concludes.

The study was first written about in August by The New York Times and surfaced again in Scientific American this week.

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