[Someone1234]

Until it is.

Ironically most of the more helpful SO google results are helpful exactly because of the discussion/updates that took place in the comment chain under an answer from ten years earlier.

> Guys how do I filter an array in JavaScript?!

>> Use XYZ

>>> XYZ works, but it doesn't work in IE5

>>>> If you're on IE10 or above you can use ABC instead of XYZ, it is cleaner!

>>>>> Hey guys, change this {} to this {}, makes it faster on mobile!

[aeorgnoieang]

Ideally, those 'discussions' would be incorporated into an answer, if only a new answer. Even-more-ideally, a single (most-upvoted) answer would incorporate all of the info from other answers and subsequent comments. That, of course, doesn't happen that often.

Every Wikipedia article has a talk page. But that doesn't mean that the purpose of the site is discussion. I think the same thing applies to SO.

[shagie]

The indents there suggest a threaded discussion that looks more like a 1 on 1 chat or threaded discussion board.

Wouldn’t one of those resources be a better place to hold such a discussion?

[sosborn]

In the best (and rarest) examples of SO, those comments percolate into the accepted answer as edits (and marked as such).