Of course, I can't speak for Kohath, so I'll defend my interpretation of the comment:
If the HDD is on, it's on. Stop mode, buffer mode, pause mode, record mode -- everything but Standby and Electrical Failure Courtesy of the Power Company mode -- the thing is spinning.
I've yet to see a HDD, though, that failed because the heads can't move. It's always been the bearings which wear out first in my experience.
HDDs, plainly, are meant to be used. From PCs to $XXmillion servers use the same type of HDDs. Doesn't really matter if they're SCSI, IDE, MFM, RLL -- they're all the same. But I've had PC IDE HDDs die just as often as Production Server SCSI HDDs.
Most detrimental to a hard drive is heat (other than dropping it 9 storeys). Keep the unit properly ventilated.
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Be nice to one another.
-m