None of us really likes honesty

None of us really likes honesty. We prefer deception —but only when it is unabashedly flattering or artfully camouflaged. Groups seem to need to believe that they are superior to others and that they have a purpose greater than just passing along their genes to the next generation. Individuals seem to need similar delusions—about who they are and why they do what they do. They need heroes, however fraudulent. People ask actors who play doctors on television what they should do for their ailments, although they know perfectly well that the actors are just playing a role. Studies show that people are more likely to accept the opinion of a confident con man than the cautious view of someone who actually knows what he is talking about. And professionals who form overconfident opinions on the basis of incorrect readings of the facts are more likely to succeed than their more competent peers who display greater doubt.

What’s more, deception works best, according to studies by psychologists, when the person doing the deceiving is fool enough to be deceived, too; that is, when he believes his own lies. That is why incompetent leaders—who are naive enough to fall for their own guff—are such a danger to civilized life. If they are modern leaders, they must delude themselves into thinking they know how to make the world a better place.

Mobs, Messiahs, and Markets: Surviving the Public Spectacle in Finance and Politics

Further in the book, Bonner writes:

Like all world improvers, Che (Guevara) claimed a remarkable ability to look into the future and then improve it before it happened. Of course, we all try to peek ahead and try to avoid traffic collisions and bad restaurants, but only a chump thinks he knows best how to improve the entire planet.