We have several questions on SFF which are of the form:
What is the work/example that is "QUALITY-iest" for a given objective property.
For example, "What is the earliest SciFi book about X", or "What is the largest (engineered) physical object dreamed of in science fiction?"
While in an out of themselves they are good questions, they have an annoying quality:
They may have an absolutely correct answer
BUT, in the process of discovering such an answer, many intermediate "best found so far" answers are posted.
Many if not most of those intermediate answers are 100% invalidated by a later posted examples
For example, for an "earliest" type question, someone posts a work from 1970. Then, someone else finds a work from 1963. Finally, someone else finds a work from 1923.
QUESTION: What should be done about those earlier, currently-clearly-wrong, answers?
The options are:
Leave them alone and let the correct "MOST-iest" answer be upvoted to the top.
Downvote them. This seems somewhat unfair to the posters, since at the time of their posting, they were the best answers. Therefore, this should be done very discriminately - for example, if a better answer was a simple Google search and TVTropes/Wiki article away, downvote is OK. This should have an exception for good quality answers that have useful information.
More drastically, prune them. Delete them completely.
Same as #3 (delete), BUT post a collected union of "could have been a contender" information either as a separate "Community owned" answer; or as an addendum to the correct answer.
I don't have a strong preference for either of #1-4 (but I strongly prefer #4 instead of #3); but think that we should have a community standard policy that can be referred to by people who wish to do the cleanup.