> Bad posters drive away good posters and encourage even worse posters, which eventually results in something akin to YouTube. Forum entropy for lack of a better term.
I've heard it labeled "evaporative cooling", per [0].
A little while back I went back to some of the newsgroups that I was a regular on, back in the 2000s. It was... a bit disturbing. I recognised a lot of the names, but the people and attitudes behind them had changed a lot: insular, cliquey, a bit xenophobic, a bit crazy.
I've seen the same attitude before in tiny SIGs: go take a look the what's left of the classic 16-bit micro (or early 32-bit micro) userbases and you'll see a lot of it. But it was very sad to see happen to people I knew and used to interact with on a daily basis.
I noticed that too, my hypothesis is one must be a little off to stay in those small, shrinking echo chamber communities for decades. In the instance I'm thinking of, some of the members did indeed have mental health issues.
I've heard it labeled "evaporative cooling", per [0].
[0] - http://lesswrong.com/lw/lr/evaporative_cooling_of_group_beli...