Businesses replace drives and systems on a schedule regardless of true wear on them - their risk vs cost metric is very different than ours.
So used business hardware is a great value for those of us who have a sunk cost in labor/expertise.
Most drives I've owned have run for 10+ years, while any business won't run them past 5. I can take the risk of losing a drive, while it's more important for a business to prevent losing a drive. Business disruption is a more costly event.