What do we do with answers made obsolete by a question change?

Question

There's a current case of an infrequent problem: Why is Donjon offline?

Dakeyras's answer was a response to a question that was once there. It was made in good faith, and is a helpful answer.

The part of the question it was responding to no longer exists, and if the question were asked in this state to begin with, Dakeyras's answer would be not an answer to any question being asked, though it's helpful.

This pattern occurs sometimes: a question is asked, answers are supplied, the question is edited, and those answers are no longer responding to the current question and may sometimes now be completely irrelevant.

What do we do in these cases? Let an irrelevant answer sit there? Ask the author of the answer to delete it? Flag it for moderator attention?

Answer 1

Generally they need to be deleted or updated.

If the author is a regular a comment indicating that the question has changed and that they should edit or delete their answer is best.

If the author is a drive by or hasn't been to the site in a while then you've got a choice to make. If a minimal edit can be made to bring it into the new scope of the question then that's best. However, if this is not possible (even if it's just too much work really), then go ahead and flag it with the "not an answer" flag or a custom message indicating that it's no longer relevant to the question as posed.

As C. Ross says in his comment, this illustrates why we need to get a question "On Hold" asap if it's in need of editing. I also highly recommend not answering questions that are undergoing scoping changes for this very reason, it creates more work for everyone involved.

Answer 2

This is why we don't like (and shouldn't answer!) questions that have multiple separate questions in them.

The fundamental solution is to not answer them in the first place before they're fixed. After the fact, updating or deleting the answer is usually the solution. In the case where the question was changed inappropriately, we roll back the question edits.

In this case, I think the error was in editing out the wrong question in the first place. Now the question isn't the sort we handle, and the answers don't match it. I think the edit should have been to keep the "where is a good fractal world generator?" question, which is on topic and one we haven't fielded yet… but what's done is done and I'd rather see it left as it is than make a larger mess of it.