Sclerosis of Empires

The heirarchy of a shitty hereditary aristocracy can't risk competition, especially in large scale human endeavors like farming or transportation. (Maybe the competition between YouTube and he shitty mainstream media, today, is a similar scenario.) In an old city, like Rome, the relationships between all the people were stuck and defined after living together for hundreds of years.

True innovation--large scale innovation, like devising new methods of motivating people, or a new religion, or a new method of farming--can completely wipe out the ruling clique of an era. Their grasping for control of resources and sunk cost in systems of control opens green fields elsewhere.