Need help understanding the point of PBS

I installed Proxmox Backup Server in a VM on my nas to see what all the fuss was about. I messed with it for a but but then the install got botched (not PBS's fault) and I didn't bother messing with it anymore. What I have been doing is, on each of my nodes, just setting up scheduled backups of VMs to a share on my NAS. I can't figure out why using PBS would be any better that just doing that but people seem to like it. I only have to do this once on each node. Could anyone enlighten me as to what I am not seeing in PBS that makes it better?