Bernie Madoff was a fan of Robert Cialdini's book Influence: The Psychology of Persuasion. Only he used Cialdini's principles for his $50 billion Ponzi scheme.Madoff used several of Cialdini's principles, but for evil instead of good. He used the authority principle because he established himself as an expert in the area of investing. Madoff presented himself as trustworthy through serving as chairman of the Nasdaq stock exchange. He also used the principle of social proof, that people want to follow the lead of those around them like them. As Cialdini points out, the recruiting always took place among individuals in their own network groups where people knew one another and let the message come from their colleagues instead of from somebody who is trying to sell a product or service. Finally, Madoff used scarcity, says Cialdini, noting that there were limited availabilities to gain access to investing with Madoff, which made those opportunities seem more valuable and exclusive. Cialdini says there are two lessons can be learned from the Bernie Madoff saga. One is the power of these rules. The second is that if you used them the way Bernie Madoff did — dishonestly — the whole thing crashes down. “It's not sustainable if used that way,” he said.
Adapted from here.