Most leaders are attracted to the guy or woman who seems confident and outgoing, unafraid in any situation or facing any challenge. They expect an extrovert to infuse any team with energy, to push ahead on projects and to motivate colleagues to do their best work. Meantime they have low expectations of anyone who appears neurotic, who seems withdrawn and too anxious to live up to their potential. Leaders expect neurotic employees to contribute little and to drag down colleagues’ morale.

Not true, says a new study by Corinne Bendersky, an associate professor at UCLA’s Anderson School of Management. In a paper called “The Downfall of Extraverts and Rise of Neurotics: The Dynamic Process of Status Allocation in Task Groups,” Bendersky and co-author Neha Parikh Shah, an assistant professor at Rutgers Business School, explodes stereotypes about how extroverts and neurotics perform on teams. It turns out that extroverts contribute less than team members expect and the contributions they do make are not valued highly over time. Neurotics, by contrast, are motivated to work hard on behalf of their teams, who wind up appreciating their efforts, in part because they exceed everyone’s expectations. In the end, extroverts decline in the teams’ esteem while neurotics rise in status.

To reach these counter-intuitive conclusions, Bendersky and Shah ran two experiments. In the first one, they broke 229 MBA students into study groups of five people and surveyed their personalities. To determine whether students were extroverted, they asked them if they agreed with statements like, “I like to have a lot of people around me,” “I really enjoy talking to people,” and “I like to be where the action is.” To identify neurotics, they used lines like, “I often feel tense and guilty,” “Sometimes I feel completely worthless,” and “When I’m under a great deal of stress sometimes I feel like I’m going to pieces.”

After the personality assessments, they had the students predict how they thought their team members would influence their groups and how team members’ status would play out in the process. The more extroverted the student, the higher their peers rated their expected influence and status. The neurotics got much lower ratings.

Then Bendersky and Shah waited for the ten-week academic quarter to pass and went back to the students to ask them how their team members had done. It turns out the extroverts disappointed their peers and lost status in the group as a result. The neurotics, by contrast, exceeded expectations and contributed more generously to the group than anyone had expected, driving their status up over time.

In the second experiment, Bendersky and Shah set up an online study with 300 people who were told they needed to make an urgent request for help preparing a work presentation from a colleague named John, who they didn’t know well. The survey described John as either extroverted, introverted, neurotic or emotionally stable. The survey then reported that John answered the request, either saying he was too busy to help much or that, even though he was busy, he would help as much as needed.

After the response from John, the survey asked about the respondents’ perception of John. As with the first experiment, respondents expected a lot from the extroverts and evaluated them quite critically if they gave an ungenerous response. By contrast they expected little of the neurotics. The ungenerous neurotics didn’t change much in the eyes of the respondents while the generous ones leapt in status. “The neurotics are rated as being more generous and exceeding expectations for the exact same response,” explains Bendersky.

What does this mean for team leaders? Bendersky says they should rethink their assumptions about how extroverts and neurotics will perform. “The extroverts are probably going to contribute less to the team and the contributions they make will be undervalued by the team,” she says. “They will do less and what they do will be under-appreciated.” By contrast, neurotics are motivated by their anxiety and feelings of inadequacy to work hard on behalf of the group. Meantime the group appreciates neurotics’ contributions because they exceed people’s low expectations.

The lesson of the study: Bendersky says team leaders should be wary of extroverts. “The core of an extroverted personality is to be attention-seeking,” she observes. “It turns out they just keep talking, they don’t listen very well and they’re not very receptive to other people’s input. They don’t contribute as much as people think they will.” If she were putting together a team, says Bendersky,“I would staff it with more neurotics and fewer extroverts than my initial instinct would lead me to do.”

The paper will be published in the April issue of the Academy of Management Journal.

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