The Quick Rollback feature can be used during a Full VM Restore to restore only the changed blocks of data since the last backup. This is typically used when the issues are minor and have been caused by VM guest user error, rather than full-scale data corruption or migrations to a different virtualization host. Quick Rollback can efficiently restore the VM to its previous state without the need to transfer the entire VM's data. Reference:

Veeam Backup & Replication User Guide: Quick Rollback

Veeam Help Center: Performing Quick Rollback