I think the world's greatest inventions have been squashed beneath the weight of obligation.
We have not yet cured cancer or established colonies on other planets or perfected teleportation because the men and women who conceived a solution to such problems have since died beneath menial chores and deadlines.
Perhaps it is no fluke that Einstein conceived General Relativity while working as a mail clerk. Many men would have liked to have done what Einstein did, but he was the only one with any free time.