Arrogance, Confidence Or Despair?

This following post is taken from Rosabeth Moss Kanter's book Confidence.

"Confidence is a sweet spot between arrogance and despair. Arrogance involves the failure to see any flaws or weaknesses, despair the failure to see any strengths. Overconfidence leads people to overshoot, to overbuild, to become irrationally exuberant or delusionally optimistic, and to assume that they are invulnerable. Thats what induces people to become complacent, leaders to neglect fundamental disciplines, investors to turn into gamblers. But under confidence is just as bad, and perhaps worse. It leads people to under invest, to under-innovate, and to assume that everything is stacked against them, so there is no point in trying."