Mathematically, taking a boss in the 10th percentile of productivity and replacing them with a supervisor in the 90th percentile was the rough equivalent of adding an extra worker to a nine-person team.
“If bosses were mere decorations, one would expect no variation” between them, the researchers write. “The fact there is wide variation…implies that there is a substantial productivity effect that bosses confer on their teams.”
So what were the good bosses doing right? The researchers considered two possibilities. Either a boss might have been really good at motivating their team (i.e., they were a cheerleader, or maybe a drill sergeant) or they might have taught employees lasting skills (i.e., they were a coach). By looking at how well workers sustained their productivity after switching supervisors, the team concluded that teaching accounted for about two-thirds of a boss’s impact on his workers’ productivity.