Originally posted by automorphism No consumer-grade storage is long term. Even CD/DVD media degrades over time, although commercially-pressed ones do last a very long time. Don't expect anything -- hard drives, USB keys, XQD cards -- to last. Instead, create multiple backups, test them and replace them as soon as they fail. This includes at least one off-site backup such as cloud storage or a couple hard drives in an external location such as a safety deposit box or self storage.
There are anomalies like glass-etched storage designed to last longer, but those are impractical for consumer use.
In fact, in terms of degradation, the most durable storage medium is actually print. Print your best shots with quality printing and they will most surely outlast any digital storage medium.
Ref "consumer-grade storage": I managed to buy 4 very lightly used "enterprise-grade" 3TB drives from a local guy on the UK AV Forums site for around £50-60 each (new price is about £200+ each!) , and they were fitted into a USB3 4-bay unit attached to a brand-new Synology NAS that went down to become the garage "off-site" storage.
All went well for 6 months and then "something" went wrong and I'm now getting to the end of rebuilding the whole shebang (all the data was also "safely" stored on the disks on another 4-bay unit in the house
) ! Don't think it was the enterprise drives, but the 4-bay unit, that "went" wrong" as the data on the disks seemed to have been mostly undamaged - I have 3 of the same model of 4-bay unit, and have found that some of the connectors on the internal PWB/PCB that can get "flakey", but hope that the several "complete" rebuilds, with contact cleaning and lubrication, thereof have solved the issues, but "time will tell".