When you only have a master and backup drive, in the case of failure, you put yourself in a critically dangerous position.<p>Restoring from backup isn&#x27;t just stressful for the human, it&#x27;s also stressful for the hardware.<p>When you have a single failure, it&#x27;s nice to at least have TWO independent backups in case during the restore there is a second failure (either due to hardware or operator).