Files are never really lost, not in the sense of being misplaced. If you save a file in the wrong place and have trouble finding it, that problem is easily solved by a disk search. It's the other ways of losing files that are harder to resolve:
1. Losing your device
Do you work on a laptop? Leave it behind in a coffee shop or cab when you're in a rush and you haven't lost just one file; you've lost all of them. Worse, if your data is unencrypted and your files contain sensitive information, your accounts and identity are vulnerable to theft.
2. Losing your data
Disk problems don't start with a full-on crash. There can be small problems that result in data corruption. This may change the data of a file or make it unreadable. You can also corrupt files if an application doesn't shut down properly.
3. Losing your disk drive
Hard drives don't last forever. They may provide digital storage, but they operate mechanically, and mechanical devices wear out. Drives' lifespans vary depending on the manufacturer, but three years is typical.