I have been using CF since 2000, IBM Microdrives, and SD since, well, when they were first needed in a camera I had, can't remember which one. In all of those years I have 1 physical card failure. I have had 2 cards, 1 Transcend CF and one Kingston CF, that had firmware incompatibilities, Transcend eventually fixed their issue, Kingston decided they were not on the CF but they sent me an equivalent SD as replacement. I have had, and have seen, a fair number of "failed" cards which were simply FAT corruption, fixed by Full Format and Error Check on a PC.
That said, I have seen enough real issues to know that some batches of cards have had issues, could be bad QA, who knows. Folks like Will, Randy and I have been lucky. Or maybe it is just Good Karma because We Three are such Good People