We have often seen how leaders who got into power because of backing from their tribe, sect or regional and ethnicities are the most corrupt ones because they knows that their people will vote for them regardless they do any good work or not. Look at African nations and even some Arab nations the reason why they are going through corruption and suffering is because people don't vote based on merit rather on personal relationship like sect, ethnicity or religion and then there comes countries like India and Pakistan where they win based on vote from majority community by instilling fear that minorities gonna rule them if not votes to power and next five years everyone suffers.
I would hold people accountable for being in an creating a corrupt leaders rather than the leaders themself.
it is very difficult before you see a good politician who is not corrupt because it is obvious that interest of politicians in a society most especially un civilized countries is to enrich their family not to do something that will profit the Citizens so we cannot blend them because they don't have the people that are leading in mind majority leaders in a country that is not civilized is performing such action everyday but their is no penalty for them because their government is corrupt