>I would like to understand why it happens so often to organizations that a currupted and dyfunctional behaviour takes over. And it seems to happen more often to institutions run by governments.

Most people want nothing more than to complete a job to the satisfaction of their supervisor and go home for the day. When you get large groups of people together, this will always be the majority. Mission driven folks will always be crowded out of a large organization, replaced by careerists who play the meta game.