In the long-term, however, the Pact bound the parties to limit Venezuela's political system to an exclusive competition between the signing parties, limiting the democratic improvement over the Pérez Jiménez regime that could have happened. The agreed rules of the Pact ensured that no matter which party won the Presidency, the others would share in power. The result was permanent coalition-style government that effectively centered power in the hands of COPEI and AD (URD leaving the Pact in 1962). Moreover, it led to future democratic erosion as COPEI and AD became increasingly corrupt, relying on oil revenues to bribe political opponents and assure their dominance over Venezuelan politics. This system would disparagingly be called "partyarchy" by critics who were even less friendly to democracy, among them Hugo Chávez.