Relative to a External player who may have years to create their build a Seasonal player is limited to 3 months or less. You are able to create so many builds because the drop rate of gear and gold is greatly accelerated to compensate for the time crunch compared to Diablo 3 at launch when it was an external only game.
Some people are simply more competitive than you. In the past we had AOZ which most people could not play at all, the Gauntlet which most people could not make the Leader board, and the higher levels of the Pit which most people cannot push to.
I understand there are people much better than me but I regard a season as successful if I can at least approach the higher levels.