"Empires do not suffer emptiness of purpose at the time of their creation. It is when they have become established that aims are lost and replaced by vague ritual." -- From Dune Messiah
The above quote captures my thoughts when I visit places which are remnants of a great civilization. It is a conversation with a past world where people knew to build great places. Those skills, those people lost to time.
But this emptiness of purpose is not limited to empires and civilizations. It is equally valid at an individual level. When you are too fixated on a purpose, to the extent that purpose is conflated with identity, what happens when the purpose is achieved?
Identity stagnates or decays sans a new purpose. New purpose implies building a new identity, letting go of past achievements, making room for new ones. When an individual thus reinvents, there comes a new time, a new empire and a new civilization as a consequence of combined efforts of such awakened individuals.