EBS volumes are "expensive" compared to S3, due to the limitations of what you can do with live block volumes + replicas, vs S3. It takes more disk space to ha

EBS volumes are "expensive" compared to S3, due to the limitations of what you can do with live block volumes + replicas, vs S3. It takes more disk space to have an image be a provisioned volume ready to be used for copy-on-write, vs having it as something backed up in S3. So the incentives aren't there vs just trying to make the volume creation process as smooth and fast as possible. I'd guess it's likely that EBS is using a tiered caching system, where they'll keep live volumes around for Copy-on-write cloning for the more popular images/snapshots, with slightly less popular images maybe stored in an EBS cache of some form, before it goes all the way back to S3. You're just not likely to end up getting a live volume level of caching until you hit a certain threshold of launches.