Which is why any discussion of this subject requires a major caveat. Yes, women suffer consequences for their lack of confidence—but when they do behave assertively, they may suffer a whole other set of consequences, ones that men don’t typically experience. Attitudes toward women are changing, and for the better, but a host of troubling research shows that they can still pay a heavier social and even professional penalty than men do for acting in a way that’s seen as aggressive. If a woman walks into her boss’s office with unsolicited opinions, speaks up first at meetings, or gives business advice above her pay grade, she risks being disliked or even—let’s be blunt—being labeled a bitch. The more a woman succeeds, the worse the vitriol seems to get. It’s not just her competence that’s called into question; it’s her very character.
—Katty Kay & Claire Shipman - The Confidence Gap, The Atlantic