OVN revert is a disaster recovery tool, only intended to be used in case the ovs-to-ovn does not succeed and the environment is on a state that can't be recovered. Also, during the backup phase, the whole controller will be backed up, so if revert is used all changes done between backup and revert that modify the state of the environment (e.g. live-migrate a VM) will create a discrepancy between the Source of truth (controllers database) and the actual state of the environment (vm is on another compute)