Although intelligence is positively correlated with inspiring and capable leadership, there's a point where a leader's IQ offers diminishing returns or can actually lead to detrimental leadership.
The findings were made by psychologists at the University of Lausanne, Switzerland, who assessed 379 mid-level leaders employed by private companies in 30 mainly European countries. The average age of the participants was 38 and 27 percent of them were women.
Each participant was asked to complete the Wonderlic Personnel Test, a cognitive ability test widely used by employers and educational institutions around the world. The average IQ of the participants was 111, which is well above the average IQ score of 100 for the general population.
Besides measuring intelligence and personality for each participant, the team led by John Antonakis also collected leadership performance ratings from eight people. These were either peers or subordinates of the executive included in the study which rated them on the Multifactor Leadership Questionnaire. This test's scores reflect a person's leadership style, which can generally be seen as useful or detrimental. Useful leadership styles include 'transformational', which inspires, or 'instrumental', which facilitates a team's goals by removing roadblocks. Passive, hands-off approaches are detrimental leadership styles.
Results suggest that, overall, women had better leadership styles, as did older leaders. The most variance, however, was due to personality and intelligence.
As previous studies showed, the Swiss researchers found that there was a linear relationship between intelligence and effective leadership -- but only up to a point. This association plateaued and then reversed at IQ 120. Leaders who scored above this threshold scored lowered on transformational and instrumental leadership than less intelligent leaders, as rated by standardized tests. Over an IQ score of 128, the poorer leadership style was plainer and statistically significant, as reported in the Journal of Applied Psychology.
It's important to note at this point at these 'very smart' leaders didn't employ detrimental leadership styles but rather just scored lower than their 'less smart' peers on useful leadership style.
The study doesn't explain why being 'too smart' can cramp a leader's style. It could be that highly intelligent leaders overestimate their subordinate's ability to carry out tasks, leading to friction. Very smart people could also be seen as outliers and, hence, less relatable by subordinates.
At the end of the day, leaders were rated by their subordinates, which could be more to blame than the leaders themselves. Ultimately, the level at which a leader performs also depends on the relative intelligence of its team members.
