In their book Why Nations Fail, Daron Acemoglu and James A. Robinson argue that societies with political arrangements that concentrate power in the hands of a few seldom excel at innovation and growth, because innovators have no guarantee they will keep the fruits of their labors. And, to the extent that outsiders cannot generate wealth, they have few resources with which to challenge the power of insiders; as a result, exclusionary political arrangements are mostly self-sustaining.