“You can amend but never erase.”
Amending is not necessary either.
Maybe it’s just me but I find it very annoying when folks post an obvious typo and 20 posts later make another post just to correct that typo. Typos are fine. If you make a mistake, just move on.
If I make a mistake, I post a correct version as soon as I can, and report the incorrect version to the moderator for deletion. I also report accidental duplicate posts. The moderators are usually very good about deleting the reported posts promptly.