Amazon made one rod for it's back itself.
Considering it started as a book company it cannot even track things by unique identifiers, like an isbn.
Instead they use an amazon product code, and they can be manipulated by third parties.
Say Big Company releases Widget 2.0 then the listing for Widget 1.0 drops out of site. But that amazonid can have something else loaded against it by a third party, they can change the picture and description - but they keep the positive feedback for the original item.
This is how I got an apple changing cable instead of a network tv tuner last year, as it was mid hijack when someone purchased my chrimbo pressie.
Or some times it's just Amazon changing suppliers and they don't fulfill orders purchased off the first amazon id.
Moving into clothing and then you are ripe for alternate supplier or overrun shifting the same as ebay. Levi's from country A appearing in country B are all frowned upon. They want to keep the brand stores and it's them insisting on this. Let alone items in different continents sizes, or kids clothes listed in with adults or visa versa.