I found this question: https://stackoverflow.com/questions/42932596/how-do-i-add-a-number-to-pandas-dataframe-index?noredirect=1#comment72966754_42932596 that I find low quality, as it is not clear what the OP is asking and does not provide a MCV example. I flagged this as a duplicate, the OP didn't accept it as he didn't get how to adapt the duplicate to his specific case, so I suggested him what to do and he solved the problem. Should I write an answer or wait for the question to be flagged as duplicate?
This example illustrates why answering in comments is the worst possible solution to these problems.
We have a down-voted question which may or may not be a duplicate (probably not), but the question seems "answered" to just about anybody looking on — in a comment — which I guess maybe helped the author maybe, but that's about it and they're gone; case closed.
But unfortunately for everyone else, comments have none of the assurance capabilities that properly vet what's been said (like proper voting and the wiki-style editing that allow us to improve that information), assuming it's correct.
I'm not picking on you specifically; but so may people feel it's justified to answer a question in comments if the post is off topic… or if they simply don't have time to work up a proper response… or if they just want to guess or post a half-baked answer that maybe someone will elaborate on later, maybe.
It's easy to see in this example why allowing folks to answer in comments essentially "breaks" the Stack Exchange model. These comments should be flagged and removed on sight to allow the process to play out as intended by this Q&A framework. Otherwise, what is the value having this Q&A format in the first place? </soapbox>