Which is why you have the safety net of the B-Grade warranty , 90 days iirc, plus - as I’ve managed to do myself - you can sometimes still register the item with the manufacturer and get a full factory warranty.
Yes B-Grade can be a lottery at times, but, a far safer one to play than chancing your luck on an item from EBay or Faceache marketplace.
Yup, I've had a few B-Grade items, and most were trouble free:
Big items:
Benq monitor, which was basically brand new, in original factory packaging, no dead pixels or anything, had 22 months of the manufacturer 24 month warranty left (confirmed with Benq).
Asus Laptop - again, basically brand new, confirmed with Asus that it had the 3 year warranty intact (less a couple of months from the original purchase date).
Also had a few odds and ends, PCIe wifi card, case, some cables etc.
The only item I had trouble with out of the box was a motherboard which was missing the m2 screw and had thermal paste all over the socket.
Also had a warranty issue with a Steelseries headset - it broke just after 12 months (common manufacturing fault), but Steelseries weren't interested at all.
In general though, people were mining on NV.
True - is that not just because they were easier to get hold of though? Either way, I wouldn't rely on a 2nd hand card not being mined on, just because it was AMD