I'm not much of technical rider, anybody can attest to that. Heck, I can't even ride backwards. Though like people better than I am, I enjoy a good cut of singletrack of moderate difficulty to ride. I've been riding at the West Hartford Reservoir since I was 11 and have seen trails evolve and mostly devolve and now I think that I have come to an understand of what happens to the poor trails there.
1) A stretch of cool single track comes into existence. The terrain at the Reservoir lends itself to good trails, so the trail might be pretty good.
2) Trails gets more popular, but it's hard. So, cheater lines and trail braids develop. However, sometimes a section was so difficult that a whole cheater trail develops.
3) Trail has become to decimated that it doesn't really have any good lines left and then people start adding stupid stunts to it. Why am I seeing people with chainsaws at the Reservoir now? I guess it's ok for maintenance, but I get the sense they're doing more than just that. Also, why are all these "jumps" so lumpy and misshapen?
I bring this up because there's newish trail that avoided a big mud pit (legitimately avoided it, it was wasn't one of those trail widening dealies). It had this tight hairpin that had a small ledge at the apex. I liked it, because it was difficult. Well, apparently most people who ride it found it too difficult and made this cheater trail that has become vastly more popular than the original trail. I tried blocking off the cheater line once, but my blocking was moved away.
There is one case where the trail degradation has helped. Someone attempted to make some bike park-esque thing off the the rt. 44 lot. It was terrible, all the "stunts" were really poorly constructed, to the point that they'd fall apart when ridden. The trail avoids them now for the most part. I guess it beats riding on the levee, but just barely.