Because the CEOs are playing a different game than you think they are playing.

CEOs are part of a club where they end up with golden parachutes - they make a lot of money even if the company does poorly - and their compensation is decided by their corporate boards, where board members are paid to be on the board.

This is true to a lesser degree in management in most companies - you become successful in management by how well you fit in and play the political games in the company. Being better at your job is not required and can actually be problematic as it makes others look bad.