How can we improve commenting on the Stack Exchange network?

Question

###The problem

Over the past few weeks, I've been thinking on-and-off that there are too many useless comments on SE sites and that people have gotten too attached to commenting. Many comments I see fall into one of these categories:

• requests for clarifications or updates
• responses to the above requests
• fluff (thank-yous, jokes and tangents)
• answers
• half-baked answers that are only comments because the posters fear downvotes
• legitimate answers in the wrong place

Today, I read two posts that brought the issue up again. This one, as part of an unrelated discussion, considers what would happen if comments were restricted. This one suggests rewarding good comments more.

Maybe, instead of rewarding good comments more, we should be more aggressive in getting rid of bad comments. As I wrote in an answer to the first post, too many people forget that comments are intended to be second-class content. (That's based on Jeff's approval of this answer, Robert's answer here and assorted other official-type remarks.)

###Solutions

Many of the example comment types I mentioned earlier can now be addressed in ways they couldn't have been just a few weeks ago.

• clarifications and updates
• Anyone can and should now edit posts (with the suggested system) to incorporate these. Once that's done, the comments that led to them can be deleted.
• answers in comments
• Mods can now convert these into real answers.
• Good answers should be reposted as real answers.
• Half-baked answers should be cleaned up and posted as real answers if possible. If they're unsalvageable, they should be deleted; keeping them around just pollutes the site.
• fluff
• Fluff should generally get deleted, although I agree that we should keep some fun around.

If we get people on board with these behaviors, most comments should become useless after a few days, which is just fine for second-class content.

My first thought for a solution was to run a job every week/month/quarter that would delete all comments more than n days old. In addition to wiping out useless requests and fluff, this would force users to change their behavior. People will think about and write comments differently if they know that all comments will eventually go poof.

Unfortunately, that plan would eliminate the rare good comments along with the bad, and would be problematic for discussion-oriented sites like MSO and Programmers SE. My second thought was to only run the script for comments with fewer than m votes. Unfortunately again, votes aren't a reliable indicator of long-term comment usefulness, and changing voting habits would be even harder than changing mindsets about comments.

Another idea would be making "vote to delete comments" a rep-based privilege, but that would probably just cause havoc.

I have no better plan yet. That's why this is a discussion and not a feature request. Thoughts?

EDIT:
What I meant by requests for clarifications/updates:

• Michael writes a post.
• Rebecca comments to say "hey, what did you mean by Foo?" or "could you include code?"
• Michael replies with the code or something like "oh, Foo is my class that fizzes the bars."
• Someone (ideally Michael, but anyone can do it, now) edits Michael's original post to include the new information.
• The comments are now safe to delete, because the important information has been turned into part of the question or answer.

Answer 1

Flagging appropriately is a positive and constructive thing for the network. We've recently made a change that allows users with high rep (showing general site knowledge) or high flag-weight (showing previous history of helpful flagging) additional moderator (etc) flags.

Going forwards, this change will also apply to comment flags, so you should be well armed to clean up the town.

Happy flagging.

Answer 2

Many comments I see fall into one of these categories:

• requests for clarifications or updates
• responses to the above requests
• fluff (thank-yous, jokes and tangents)

The purpose of the comments system is to give people an outlet for these things, so that we can keep them out of questions and answers.

Comments are also good for some half-baked answers that are not real answers, if they point the OP in the right direction.

Answer 3

Comments as a relief valve

While comments are second class citizens, they are an important safety valve for the site, so I'm against anything that actively discourages comments, even if they are fluff. I'd rather have users posting fluff comments because they just have to post something they found relevant, funny, etc, rather than having that extra fluff end up somewhere else. If we actively discourage such comments (by regular deletion, easier ways to flag and delete, etc) then we'll end up with that extra fluff going elsewhere, and not in a good way.

Please note that people who are attracted to question and answer sites are relevance machines. We know all sorts of interesting and uninteresting facts, and our brains are tweaked to find relationships between disparate pieces of information - it's exceptional for problem solving, but also leads to a lot of useless banter.

In addition to being a safety relief valve, comments, though second class citizens, are still citizens and are an accepted way to bring relevant and useful information into a discussion.

Yes, ideally relevant information would be contained in the answers, but that's not always true, and more importantly it's not always appropriate. A question about X may result in an answer Y(X), which may result in a comment Z(Y) and while the comment is two functions removed from the question, and arguably not directly related to the question, it does sometimes lead the OP to a new piece of information that helps them resolve X. Posted as an answer, though, it would be downvoted as it doesn't directly address the question.

Clarifications

Therefore I can't agree that every comment of value should be rolled into an answer. Even clarifications are annoying. I've often had people ask for clarification, and I've provided it, but I don't roll it into the answer because it complicates the answer, makes it longer than it needs to be, is tangential, etc. However, it's still valuable in its own way, and therefore shouldn't be deleted.

Answers as comments

In the case of a semi-answer I vote keep it around as a comment. Just because it may not have evolved into the solution for this question doesn't mean that some intrepid google born traveler won't find that it answers their peculiar related problem, or at least sets them thinking on the right path.

Fluff

You and I both agree that some fluff should be kept around. I do not want to live in a sterile environment where we are limited so severely in our forms of interaction. Sure, you and I could both find some fluff to get rid of that we'd agree on, but there's probably a lot of fluff you'd keep around that I wouldn't and vice versa. I don't think we can easily separate the wheat from the chaff in a way that wouldn't offend people.

Conclusion

The upshot is that I don't see the harm these comments are doing to the community. I think we'd need to have a higher level of comment unhappiness before we really start to chop away at commenting.

Answer 4

Another idea would be making "vote to delete comments" a rep-based privilege, but that would probably just cause havoc.

This already exists. Just flag the comment - that's a vote to delete...

...Unfortunately, we only get a handful of them, and there are a lot of comments. On top of that, some users are reluctant to flag things purely for being "noise".

In response to the first problem, I've suggested that we really Need more comment flags!

In response to the latter problem... Well, actually, I'm not convinced it is a problem. I mean, what's the worst-case scenario here? Little bits of useless text that the site already hides by default? It's really not that big of a deal.

You already note that editing could replace some of this... But it already does - at this point, just about any user can take a bit of clarification from a comment and edit it into the post itself. Yes, the comment remains... But so what? It's hidden, and bytes are cheap. Similarly, anyone posting a valid answer in a comment should expect that someone else will eventually post it as an answer (assuming they don't do so themselves).

And in the very, very worst cases, moderators can easily wipe comments, either selectively or en masse. Just... flag.