There are a number of built-in protections to prevent abuse of the edit feature.
If you edit a post, three things happen:
-Everyone who interacted with the post gets a notification to say it's been edited
-An "Edited" notice appears below the post
-A history of all the past versions of the post are created, which can be accessed by clicking on the "edited" notice
If the post is re-edited, the notification is repeated and the new version is added to the history.