Perhaps wear & tear from regular use increases the likelihood of a "busy" drive failing. But in my experience it hasn't worked out that way. I strongly suspect variations in manufacturing and quality control have more to do with a drive going south than wear and tear does.-40hz
That tracks with my experience also. The head/platter relationship is zero contact, so nothing there can really "wearout". But if the thing is spinning, the bearings are making physical contact, and are indeed wearing slowly out.
Only exception I can think of is if something is being badly overused so the read/write lifetime is exceeded in a localized fashion. Like an XP SP2 machine with 256MB RAM from the factory ... They seemed to have an odd habit of blowing a hole in the drive wear the pagefile wasn't anymore.