Sometimes with digital, the failure is in the medium, not in the handling by the photographer. I do multiple backups of all my digital images but what happens when the tragedy occurs before you can back them up - or even accidentally delete them?
Last weekend I shot a wedding for a good friend of mine with my Nikon D7000. After using the same memory card for ~500 shots all day long, I was about to shoot the bride tossing her bouquet. My camera wouldn't fire. At first I thought the problem was the AF in the dim light, but when I looked down the LCD was flashing "Err." I quickly swapped cards and kept going. On the ride back to our hotel, I tried to view the contents of the original card, only to see an error on the rear display that the card was damaged and to insert another! I felt literally sick at the prospect of losing all the wedding, formal and much of the reception shots.
When I got back to the room, I immediately tried the card in my laptop. The files were visible, but importing them directly into Lightroom prompted a BSOD. I restarted and was able to copy them manually to the hard drive then import them into LR afterward. Thankfully, I didn't lose any photos despite an evidently flaky/ failing card (Kingston 32GB). I've never had an SD card fail like that, and I'm always careful to reformat them in camera after each use. The night could easily have ended in disaster if my efforts to recover the files had failed.
While I could have potentially added some safety steps (using multiple, smaller SD cards and/or using two cards at once instead of leaving card 2 as spillover), the incident was a reminder of just how fragile those 1s and 0s are. Sure, you can mess up a roll of film. But at most you've lost 36 exposures, not 500. And even then, chances are you could recover some image in many situations. But bits and bytes do not a photo make, and until you've got multiple backups - and preferably real prints - they're just digital files.