Recently, lots of comments (which were not offensive or spam) got deleted from this question: Why doesn't Chewbacca learn to speak Galactic Basic?
And, people are complaining in chat. I also didn't like it. Notably, I have raised comments deletion issues before (and, there's always others who also felt bad). This time, I am proposing to enforce a policy which should override the generic guideline of comments deletion.
Right now, mods are doing whatever they want. Sometimes, they delete a long thread of comments and sometimes they don't. Sometimes, it makes us happy and sometimes it pisses us up. I won't blame mods. The problem is with the rules. I am requesting the community to enforce a policy regarding this.
Please, post your policy you want enforced as answer and let community vote. Here are some examples (not applicable for offensive, spam etc comments):
Delete comments only after a week.
Delete comments only if the discussion thread crosses x number of comments.
Always push comments to a chat room. Never permanently delete.
Don't touch the comments. The community has grown far from the initial vision of SO founders. Maybe, their logic isn't working well due to nature of this site.
Ask for consent of the post author before deleting comments on it.
Discuss in chat before deleting comments.
____________________ (fill in the blanks with your creativity)