This site is one featured on a recent series on the History Channel on Ancient Aliens. They note the precise cutting of the original ring stones and the location being difficult to maintain a large population necessary to manually raise and carve the stone.
But as this article states: “Bewilderingly, the people at Göbekli Tepe got steadily worse at temple building. The earliest rings are the biggest and most sophisticated, technically and artistically. As time went by, the pillars became smaller, simpler, and were mounted with less and less care. Finally the effort seems to have petered out altogether by 8200 B.C. Göbekli Tepe was all fall and no rise.”
Lets make an analogy to the ‘cargo cults’ of the Paicific islands where primitive societies were exposed to artifacts (planes & goods) from a more advanced society that dropped in, made some friends, and then took off. The islanders tried to lure them back with crude copies of the planes.
Now stay with my analogy for a minute: In Gobekli Tepe you have a second ring, less sophisticated than the first as skills are lost and then a third ring even more crudely done and finally when the ‘Gods” don’t come back, the religious loss of faith occurs and the effort is abandoned.
I love this stuff!
I don't know that this is so bewildering. I think of the knowledge that was known to the Classical world that was lost as Europe descended into the Dark Ages that wasn't found again until the Renaissance.
We live in a world of lost knowledge.