I'm a completionist (sorry) and I did something that I think, by definition, should have awarded me the Excavator badge (Edit first post that was inactive for 6 months) here. Do abandoned buildings sort themselves out eventually if you just leave them?
I edited my answer from Mar-2015 to add a V2 of a plugin I suggested. The edit passed and is now shown. But the Excavator badge was not awarded. What did I not do right?
PS: The last time the post was even toutched was Dec-2015. So even if by post it meant the question and all it's answers it should be right?