“After going through that experience, Woolley had an epiphany: financial institutions that react to market incentives in a competitive setting often end up making a mess of things. “I realized we were acting rationally and optimally,” he said. “The clients were acting rationally and optimally. And the outcome was a complete Horlicks.” Financial markets, far from being efficient, as most economists and policymakers at the time believed, were grossly inefficient. “And once you recognize that markets are inefficient a lot of things change.”

Wall Street, investment bankers, and social good : The New Yorker.