First of all: I do not want to blame someone, so the example here is only an example no statement against a person!
Have a look at this revision 3 to a question:
As you can see, someone asked a question, got answers and then he/she has rewritten the question to something completely different using the answer(s) they have already got. Now the old answers, which were useful for answering the original question, are more or less no longer useful for the new question.
Should we revert this question to the original one (and also delete new answers to the new question) or should we accept the question as it is now and delete the old answers?
I'm not asking about what to do, if someone has a follow-up question. We all know, that he/she should ask a new question. But what to do, if someone has not asked a follow-up question but replaced his/her original question by a new one.