Confession time: I once lost three months of photos to a memory card that got corrupted. Obviously, I should have backed them up somewhere else, or at the very least printed them out. It was my fault, and I'm not in any way looking for sympathy. The reason I share this is a cautionary tale. Not only can this happen to you, it very likely will.
At the time, it felt like my whole world had collapsed. Could I ever trust tech again? I started to see everything from memory cards to hard drives in a new light. Not a guarantee, not even a promise to protect my data. More of a shrug and "Well, hopefully it won't go wrong...".
