Shit happens at scale, it's precisely why ACID guarantees are important. Specifically in GitLab's case, because configuration is stored under /etc/gitlab, relying on EBS snapshots as a safeguard against corruption only works if the snapshot is taken of the entire FS, not just /var/opt/gitlab. If your machine is properly provisioned from an AMI or at least from some kind of configuration management, and you have some kind of reasonably-enforced policy which only permits changes through those management systems, then maybe you can get away with only taking a snapshot of /var/opt/gitlab, but now we're getting into the territory of "I understand how my data is being stored to the EBS volume (in this case, according to documented GitLab instructions) and I am acting accordingly". Then, if the /var/opt/gitlab snapshot ends up being corrupted, the odds of getting an uncorrupted snapshot increase with the more snapshots that you try, and this is probably good-enough in this specific instance because if you needed a better guarantee than that, you'd have a proper HA setup.