bosses: what do your employees complain about behind your back?

When I'm interviewing candidates for management positions, I like to ask something like: "Even the best bosses' employees will occasionally have complaints about them. What complaints do you think the people you've managed have had about you?"

The responses are revealing in a lot of ways. An astonishing number of people can't answer it at all, or have to really think about it; they've clearly never bothered to think about it before. This is disturbing, as it indicates anything from lack of self-insight to insufficient engagement with employees to simply not caring what employees think. A handful of people will say what they think I want to hear, usually something along the lines of, "I work them too hard." (Not what I actually want to hear, by the way.) Of the people who can answer it genuinely, I've heard responses ranging from "I can be too gruff" to "They want more direction." It's really a useful question for getting insight into someone's management style -- or, in the case of the non-answerers, their lack of insight into it.