I tried that once a couple months ago. The drive pretty much came with a head crash preinstalled. I plugged it in and it sounded like it's shredding bricks in there.

I assume the seller just sources defective drives from somewhere and directly resells them as refurbished, letting the buyer do the actual testing. I assume this must work because some drives might erroneously been marked defective when it was really a sofstware issue, or other hw problem, like faulty sata cable, mainboard, loose connection, and then obviously there are drives with minor issues, like just a few reallocated sectors, that the naive buyer might not be aware of.

Yeah, I don't know what Amazon Renewed is, but it's not consistent. I bought two renewed phones of the same model a couple weeks apart, and they came with similar but not the same packaging, and one came with a review card from the vendor, even though I bought shipped and sold by Amazon.

I think they're going to get in trouble for it (and Amazon Choice) because it implies they're the ones doing the work.