I started shooting digital in the year 2000. Never in that ten plus years of using memory cards have I ever had one fail. I even have a 64MB SmartMedia card from my first camera that still works. One time the 5-year-old 2GB Compact Flash card in my Nikon D70s got fidgety and lost a couple shots after I used it in a card reader, but once I cleaned the contacts in the Nikon and reformatted the card, I haven't had any other issues with it.
I've had this 16GB Class 6 SD card for at least three years. I originally purchased it when I bought my Canon HF100 video camera.
I recently upgraded the Canon to a 32GB card, so I moved this one to the Leica M8. It handled thousands of pictures over the past month with no problem. Then last night, I was snapping photos of my niece when the M8 stopped previewing photos after I shot them. The red light was flashing and the camera locked up after taking only three shots in rapid succession. After pulling the battery to reset the camera, I was only able to see about half of the photos I took, the others just displayed the file name. However, the card was still reading in the camera and allowing me to take more photos. At that point, the photos were still salvageable. (Note: If your camera starts doing this, and the photos are important, stop using that card immediately and run it through a memory card recovery program.)
Not thinking it was serious, I decided just to reformat the card in the camera to get rid of whatever glitch was going on with it and to shoot all the photos again. That's when I started getting the following message when I turned on the camera.
Of course, if I hit the Play button, it would then give me this message.
My card was dead. I didn't have a spare.
When I got home I popped the card in my Leica X1 to see what would happen. It immediately asked me if I wanted to format the card. I said, yes, thinking maybe I could still save the card and bring it back to life. No luck. The X1 couldn't format or read the card either.
This morning I downloaded CardRecovery to scan the card. Of 33554432 sectors scanned, 33229318 sectors showed up bad. Nothing was recoverable.
Lesson learned -- always have a backup memory card. I don't trust hard drives any farther than I can throw them. I don't expect them to last more than two years. However, I've never worried about flash memory before. I've obviously become too complacent. Then again, one card failure in ten years isn't too bad. I just hope the M8 doesn't start eating memory cards the way the M9s have been. I think it's cheaper to go back to film than to have to pay for a new card every shoot.