Hard drives 5 years; yeah it happens but then usually fast after active use: if they do not fail fast then they usually keep going. I have 100s of HD's here from 25 to a few years ago and most of them work fine. Especially the 90s/00s then-expensive scsi discs do not seem to fail. But cheap internal and external HD's from that time are also still all working. If they get beyond 5 years (and by far most do), they get to 20. Anecdotal ofcourse.