Online communities often go from a small, enthusiastic, intelligent niche group that is relatively self-policing to a larger, amorphous group that becomes stupider at a rate that’s an exponent of the number of users (the linked book is excellent on this topic). Initial moderators are usually enthusiasts and small groups are more like communities than cities. Later moderators are usually adversely selected: What kind of person would voluntarily spend lots of time and energy policing a community for no money? Consequently, online community decline is often exacerbated by the moderator or moderators who eventually take over or seek power.
The psychology of someone who is willing to moderate a Reddit subsection—or any similar site, like many mailing lists—is probably not good. It takes someone willing to spend a fair amount of time at a thankless task that is hard to do well and rarely if ever remunerative.
A lot of the people who start at that task do so optimistically but quit as their lives change or the task becomes more onerous. Who gets left? People with axes to grind; people with no sense of perspective; petty tyrants; and so on. I don’t use Reddit much for many reasons, but low moderator quality is one. I rarely bother messaging them because doing so is largely a waste of time.
The problem with moderators is not dissimilar from the problem of users: People who regularly have something interesting to say and the means to say it well get blogs, as I wrote in Social news sites and forums should encourage users to blog. Those who don’t stay on Reddit. The average contributor to Reddit doesn’t have a lot of stake in long-term reputation—as bloggers, journalists, and academics often do—and that shows in the quality and quantity of posts. That may not hurt the site—the popularity of bad TV shows over many years demonstrates lowest-common denominator issues—but it should hurt it in terms of high-quality users.
A form of Gresham’s Law applies to social sites and to moderators: bad commentary pushes out the good, and smart people flee stupid comments. One could alternately call this a tragedy of the commons, in which communal spaces become overrun with spam or commentary so stupid that it might as well be spam.
Reddit and similar sites can have an orthogonal problem, however, as they become so afraid of self-interested commentary or posts that they forbid it—thus causing smart people to go elsewhere with their thoughts, and leaving the dregs unwilling or able to create standalone communities or blogs.
This may be part of the reason why Reddit—even on the “good” subsections—tend to be better for beginners: anyone who gets past the beginning stages needs more expert advice than Redditors can provide. The same is happening to Hacker News, too, or it has already happened, though not as severely: Hacker News has an advantage in that its survival and the intelligent commentary on it is tied to a business that is in turn tied to ideas. Its moderators have a stronger incentive to get it right, since they’re not driven primarily by ego or overwhelming fear of “spam.”
That being said, anyone who has seen an unmoderated forum is aware of the fact that unmoderated forums are unusable. So getting rid of moderators is not a solution. In general the mechanisms of exit, voice, and loyalty, as described by Hirshman at the link, apply on the level of online communities. But constantly shifting for newer communities where smart people congregate is at best difficult and at worst a waste of time in and of itself. Reddit has to some extent worked on this problem through the sub-Reddit system, which is a better-than-nothing solution but not a great one.
Maybe there is no good solution to this from the perspective of smart users other than withdrawal. Better blogs written by smart individuals or groups are better than virtually any online, Reddit-like community I’ve found. Which is too bad. But I doubt most people in latter-day moderator positions are even willing or able to read this post, and, if they are, I don’t think they’ll understand it, and, if they do, I don’t think they’ll accept any of it.