Both are true, but both are true for internal combustion engines too. We have platinum in the catalytic converters, and engines last the projected life of the

Both are true, but both are true for internal combustion engines too. We have platinum in the catalytic converters, and engines last the projected life of the vehicle. From what I've read, fuel cells are being designed for similar lifespans. As with many things, internal combustion engines included, we can choose how long they're designed to last, that's a design input. If they have limited lifetimes they're designed as such. If we want longer lifetimes, we just design them to achieve that.