# Suspicious deletion of a comment

I wrote a comment on this question and after a while it has been removed.

On planar $4$ regular graphs

There is a 1% chance of accidental deletion of that comment by me. Other than that it should have been deleted by someone with sufficient access.

Before completing my complain, I'll first explain the story. Sasho raised one question and one answer on his first comment: he was not sure why a particular part of some paper is correct and he was thinking that paper answers the question. Then I spent time to look at that paper and first I explained why that part is correct then asked why Sasho thinks that answers the question. Then Sasho understand his mistake and I don't know why, he or someone else removed his comment and then he answered me. Then I just upvoted his comment to say I'm agree with you.

When I looked back at the question, I've noticed my comment has been removed. I think I didn't do that, unless unexpectedly I pressed the delete button. I'm wondering why someone should flag that comment or remove it?

I personally do not delete my own comments when someone provides a constructive answer to me, because, that answer might be helpful for others in the future. However, even if someone removes his own comment why should a constructive answer to that comment be deleted?

In the aforementioned case, even if after deletion of the first comment, someone doesn't understand what I'm answering, could ask it in a new comment.

It looks like the comment in question was

@SashoNikolov, I think, in any 3-coloring, nodes x and y should be colored same as the middle node in the picture (they didn't name it, but there is a unique node in the middle of the figure 3). However, I don't understand how this paper answers the question?

Often what happens is that someone flags a comment as "No longer needed" if it is in response to an already deleted comment or if it asks for something that has already been provided. Deleting such comments helps the site look less cluttered.

It can be tricky because sometimes the comment is valuable even when it's in response to something already deleted.

One piece of general advice is to edit valuable information into Questions & Answers. There is a common view that comments are ephemeral on StackExchange sites, but it's a balancing act.

• In the question, I've explicitly asked why the comment has been flagged. E.g. to make the question a bit more clear, consider this comment of Sasho cstheory.stackexchange.com/questions/44005/ it has no extra information except responding to my comment. However, it is neither flagged nor has been deleted, it means the decision taken by community and administrators is biased. On the other hand, my comment was useful for perhaps someone else who may face the same issue. It also was not an answer to the original question. In general, admins should not delete a flagged comment (semi-)blindly Jun 11, 2019 at 8:10