Forever is, as Prince once pointed out, a mighty long time. Requiring periodic renewal ensures that the entity that is responsible for the domain is still aliv

Forever is, as Prince once pointed out, a mighty long time. Requiring periodic renewal ensures that the entity that is responsible for the domain is still alive, and still wants it. Allowing an entity to register a domain forever creates the possibility of zombie domains, registered forever through a registrar who has long since gone bust, by a registrant who long ago lost their password... but the registry is obliged to still maintain the last state of that domain's NS records forever. Nobody would be able to initiate a transfer; nobody would be able to buy the domain off the owner... the resource would be permanently dead.