Over-confidence is one of the most fundamental mistakes that an aspiring leader can make, a survey of US workers has revealed.
The research, published today in the Journal of Personality and Social Psychology, says that successful bosses must employ just the correct amount of assertiveness, as a low level of self-assuredness was also cited as a problem.
Lead study author Daniel Ames from the Columbia Business School writes that excessive or insufficient assertiveness was the most common attribute mentioned by respondents as their bosses' greatest weaknesses.
Intelligence, self-discipline and charisma emerged as the most widespread desired leadership traits, with the reverses emerging as commonly-cited faults.
"Assertiveness dominated reports of leadership weaknesses, though it wasn't nearly as common in colleagues' comments about strengths. When leaders get assertiveness wrong, it's glaring and obvious, but when they get it right, it seems to disappear," Professor Ames writes.
"We say it's like salt in a sauce: when there's too much or too little, it's hard to notice anything else, but when it's just right, you notice the other flavours. No one compliments a sauce for being perfectly salted, and it's just as unusual for a leader's perfect touch with assertiveness to attract much notice."
But he cautioned that many leaders would be wholly unaware that their behaviour was over-assertive due to a lack of candid feedback.
He writes: "Who wants to tell the overbearing boss that he or she is a jerk?"