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by nommm-nommm 3773 days ago
>Look, this is a stupid bug in their algorithm, and will probably be fixed at some point.

I don't think its actually a bug, it's just the way Amazon sales rank works.

http://onlinesalesstepbystep.com/rank-risk-reward/

"I can define Amazon sales rank in one sentence:

“The period of time since an item last sold.”

That’s it

What does that mean? It means that starting from one hour after an item sells, its rank will start to rise until it sells again. The longer the gap between sales, the higher its sales rank grows. When the product sells again, it will drop significantly and then begin to rise again an hour later."

https://sellerengine.com/top-5-things-you-need-to-know-about...

"2. Current Sales Rank CAN’T Tell You How Well an Item is Selling

Because of the huge swings that sales rank can undergo (see the previous graph), looking at a single data point can’t tell you how well an item is selling. A low sales rank (one that is close to 1), can trick you into thinking an item is a longtime popular seller, when actually, that item was just sold.

To make accurate guesses about how fast an item is selling, you need to look at multiple data points and see how an item’s sales rank trends over time."

All products on Amazon have a sales rank, not just books. I'm not really sure of the reason for publishing it but it isn't supposed to be scientific or anything (the exact algorithm is not disclosed). All categories have a sales rank and a best seller list, no matter how obscure and the sales rank has worked this way forever. Why? I don't know.