I once read an article about forum quality as a function of the number of users. I can't seem to find it anymore, sadly.

The core idea is there's an optimal number of people. Not enough people and the community dies: not enough activity and ideas to sustain it. Too many and it also dies: it becomes impossible to form social relationships, cooperation dies down, everything becomes meaningless because you don't know anyone, the probability of ever interacting with any given person ever again trends toward zero.

Made a lot of sense to me.

Yeah, it makes a lot of sense. Curious to know what that article was. Was it an actual study or just some random post?

would be nice to find it :P