One thing to note here, too, is that staff have a lot of
experience in seeing things go downhill from a post. We've gotten a good feel for things that can easily turn discussions off topic or into flame wars or cider press stuff. So, we often nip things in the bud, things you might not expect to be bad. You might think a post is perfectly nice, but moderators can tell that it will bring a lot of not-niceness. So we deal with it before we have 20 not nice posts to delete and then we have to lock a
thread or something because people just wouldn't stop being not-nice to each other.
As for giving explanations for moderation decisions, we have the ability to do that through "Almost-a-Post"... but, a lot of people don't respond well to that. Instead of going "Oh, okay, I'll change that, thanks!" They go "THAT'S WRONG and YOU'RE ALL HORRIBLE and I WILL NOT
CENSOR MYSELF and YOU EAT BUGGERS FOR BREAKFAST!!! And your feet smell, too!" So, when people don't respond well to moderation, we don't even try to Almost-a-Posting their stuff.
I have, personally, had people blow up in my face countless amounts of times for very nicely, politely worded Almost-a-Post messages. It's extremely disheartening and feels like a slap in the face. And, often those people storm and make a larger fuss and leave the site far more than when we just silently delete their post. So, I don't try them nearly as much as I used to. I think a lot of staff are burnt from such reactions in the past as well, too.
So, if we do use Almost-A-Post and give reasons for our moderation, it's only for really great posts that need small amount of tinkering, and only when those posts are written by people who seem like they're respond positively to it. Otherwise, we just delete.
As for knowing who did the moderating, I don't think it
should matter. We staff stand beside one another and spend hours a day discussing moderation decisions. We work very hard to support and help each other make the best decisions, and we're not throwing someone under the bus by letting people know who did the moderating decision. That would not be nice. This site would be a whole lot worse if we staff weren't nice to each other.
Also, there's been a few times when someone decided they "knew" who did the moderating (and they're almost always wrong in who they assume did it) and they go send their chosen staff member nasty PMs. No staff member needs that. Telling people who did the moderating decision would only make this far, far worse. Staff work really, really hard as volunteers to make this site lovely. There is a LOT of stuff we do behind the scenes. So much so, that when we bring on new staff, they usually have deer-in-the-headlights look on their faces because they had no idea how much we do, and it's overwhelming. We work really hard to support them and train them (and we do it entirely unpaid), and we don't need them burning out because people send them nasty PMs.