Older techies/digital photographers can pull out a drawer with tons of old SD and CF cards, and the truth is most find their data completely readable. I have some from 2000 (ex: a 16mb card - yes, megabytes) that still have old intact WordPerfect and Wordstar files read by my universal reader software. With that said, SD cards were never designed for cold storage. Can you read thousands of anecdotal stories of failure? Yes! However, retention of data on these cards is much greater than a few of the responses here would lead you to believe. Look at any photography subreddit and you’ll see when asked about SD failures that most say none, one, or two out of dozens and dozens, even 100+ cards used. The real-world endurance of high quality flash is pretty damn good. The vast majority of these cards last up to their rated 10 years and beyond. The key is buying from quality manufacturers and not buying their “economy” lines sold in some parts of the world. Never buy generic. But, when dealing with any kind of storage medium - the key word, beyond anything else is: backup.