Unless you're completely new to commenting on MN and therefore aren't aware you can:
a) see how many pages of comments have already been made, and therefore check them before commenting, and:
b) click to read all of the OP's responses and updates
Why do you blithely ignore (what are often) reems and reems of comments and relevant responses from the OPs to put your two penneth'orth on a long-passed or clarified original post, usually parroting what multiple others have already written?
We've seen a great example of this yesterday, on the post written by a poor lady in the ME whose husband had clearly not really been in a barber shop for the two hours he'd said he'd be. We're currently on 36 pages of comments on this particular post, and we still have people commenting on the OP's original point, ignoring everything else she's since written (and in many cases being extremely unfair and nasty to her), promoting dozens of other people to kindly leap to her defense and ask these latecomers to read the entire thread before commenting.
What a mess.