Similar to GitHub, where code versioning is a thing, Beatmap versioning should be fairly useful in the mapping scene as it allows for rollback of map in case anything goes wrong, and this feature is especially useful towards map hosts as it allows them to 'share' permissions with their map guests for them to submit and edit their own difficulty as per the hosts permission. This allows for collaboration between map host and mappers who are doing a guest difficulty and allows for tracking of map completion, etc and also improves the convenience of both the map host and the mappers doing Guest difficulties.