Mediocrity & Genghis

There is something to be said of mediocrity. Mediocrity allows respite from expectation. It allows you to maintain shelter from the masses.
But mediocrity is not something that people want. Noone, as a child, proclaims:

"I hope I am mediocre."

Noone lusts after a mediocre man. Those that (ostensibly) do are either out of options and desperate for companionship, or mediocre themselves.
Why is this the case? Why do we, as a species, despise mediocrity? Perhaps evolution is to blame. The gradual honing of our species towards greatness. And the curious phenomenon of the leaders of our society, the truly great, taking countless wives and fathering endless offspring. The gradual, systematic, genetic eradication of the mediocre.

Perhaps Genghis Khan is to blame. I read somewhere that 1/2 of Europe can trace their lineage to Genghis (I have no evidence for this claim). And there is no doubt that Genghis was anything but mediocre. His influence was spectacular.

Perhaps prior to Genghis mediocrity was far more accepted, even celebrated. There is something noble about the man who is content with his lot in life, who accepts that the Earth holds finite resources and every dollar more he controls is a dollar less for someone else. I admire that man, for I do not think I could be him.