The "Perfect Demon" is one that uses every advantage to gather power, favors, and to slowly but steadily climb up the social power scale. The goal should always be the next rung, not looking too far ahead or becoming complacent with where one is currently.

In practice most Demons simply do not have the intelligence, energy regulation, or patience to continue their climb indefinitely. Most stall out, spinning their wheels in a grinding war of attrition that results in decades going by with very little change in power or position, or a slow descent into impdom.

The pyramidal shape of power also only allows so many Demons to exist at the top, so if too many Demons climb too quickly then a certain amount of "pruning" must occur, at the behest of the reigning Demon Masters.

Once the Demonic population passes a threshold of power and numbers then a certain amount will be sent out into the Human world, to flourish and die, and then the cycle begins again.

This system has allowed for a stable Demonic population to exist for hundreds of years, slowly cycling power up and out, while the Demonic Masters remain stable in their control.

It will do, for now.

-Notes on The Age of Sloth, by the Demon Master The HeadMaster