A combined "infant mortality" and "wear out curve" to make a bathtub curve seems plausible for SSD. "useful life" of 5 years implies that the wear out curve has

A combined "infant mortality" and "wear out curve" to make a bathtub curve seems plausible for SSD. "useful life" of 5 years implies that the wear out curve has risen significantly at 5 years. I suppose if there are few units that will make it into the thousands of years they can balance it out. Perhaps they take 10% of the production, pack them in inert gas shielded inside a meter of lead and bury them deep in salt mines to keep the MTBF up.