If I flag something (at least as VLQ, maybe other flags too?) and somebody edits the post, my flag is "resolved" (disputed) and does no further harm. If I vote to close (or reopen) and not enough people agree, those votes evaporate after a few days. (And close votes can be revoked manually if I want.) But delete votes are forever, even if the post is edited and substantially improved, with no way to revoke. Why is that? I'm asking about delete votes on both questions and answers.
(I've seen this question, which seems to be mainly raising a "fairness" issue with reopen vs. delete. I'm more interested in why delete votes, apparently uniquely, are permanent.)