People forget that flash memory uses electrical charge to store data. It’s not durable. If left unpowered for too long, that data will get corrupted.
Yeah, but the link in the article, strict checks and no data loss over 52 weeks. Not neccessarily in USB sticks though. And sure, backups.
Note though that usb Sticks (if you mean that with USB drives) usually get the worst, cheapest quality flash. It’s a lottery, and expect nothing in no-name sticks.
* quality in yield, ssd > sd-card/emmc > flash sticks