The mistakes (of leaders) are amplified by the numbers who follow them without question. Charismatic leaders tend to build up followings, power structures and these power structures tend to be taken over by people who are corruptible. I don't think that the old saw about 'power corrupts and absolute power corrupts absolutely' is accurate: I think power attracts the corruptible.
Frank HerbertThe gravest error a thinking person can make is to believe that one particular version of history is absolute fact. History is recorded by a series of observers, none of whom is impartial. The facts are distorted by sheer passage of time and thousands of years of humanity's dark ages, deliberate misrepresentations by religious sects, and the inevitable corruption that comes from an accumulation of careless mistakes. The wise person, then, views history as a set of lessons to be learned, choices and ramifications to be considered and discussed, and mistakes that should never again be made.
Frank Herbert