This "feature" of Reddit has always really bothered me. Who is Reddit helping when a user's comment is removed but they're tricked into thinking it's still up?
It's a tactic against spammers and trolls. It's believed that they are not as likely to continue the behavior as they would if they saw the immediate consequence of their actions.
Good question. Research suggests providing removal explanations [on posts] results in less work for mods [1]. And more research into reddit moderation is on the way [2].
The first time silent removals were discussed on reddit was apparently in 2007,
> "A better idea is a silent ban. Let him post comments" [3] (found via [3.a])
In 2010 reddit's CTO said he supports silent bans [4] after a blogger discovered they had been silently banned. And the CEO in 2017 said it was necessary [5], then in 2018 said,
> If we knew everything everything we know today about spam, enforcement, and transparency, we probably wouldn’t build shadow-banning. It’s use is really limited to spam, and I think the downsides (false positives, lack of transparency) outweigh the benefits.
> That said, it was useful in the early days when spam was more of an arms race, we didn’t have moderators or reporting, and our content policy was limited to spam. [6]
How exactly? It's not like the only other option is "always assume bad faith".
Since reality is a bit more complex, I think such things should be decided on a case by case basis. I've seen plenty of both extremes here on HN, and tons of unknowns
By being an effective moderation tool. I like shadowbanning more than a simple ban, because I think it works better by not giving the bad actor an instant response. They can't use the feedback for further bad action, creating a sense of confusion, or being ignored. And then if we suppose that it works well, then with other useful tools in the moderators' bag of tricks, they can do a good job keeping a community's discussion above a certain level, thereby benefiting the community at a larger scale. I'm sure that if used in bad faith, it can be used to control a narrative, but in this regard it doesn't do a better job than other moderation tools, like editing a comment or banning users.