"Humility ... is the grace note of leadership."
I love that sentence in John Baldoni's article at darwinmag.com. If you've ever labored under an always-right leader (and who hasn't?), you understand it only too well. As discussed in The Leader's Voice, it's often the cover-up, not the foul-up, that crashes careers. I'm sure we can all name a few folks who've learned this lesson the hard way.