Volume backup/snapshots and resiliency

I’ve been trying to figure out how resilient the volume snapshot feature is. Do snapshots survive the failure of the physical NVME storage device holding the volume? Are these stored in the same region but on a separate machine? I am not too worried about a data center failure, those happen, but tend not to destroy data, I am more worried about a device failure. Do I need to roll my own backup to a different region?