In Europe there’s a law that forces stores (online but also physical) to post also the lowest minimum price in the last month.
So it would be
€199€64 (lowest price in the last 30 days: €39)Amazon US doesn’t do that, but they do show a “lowest price in 30 days” badge that is actually truthful (appears when the item is on sale and the sale price is the lowest in the last 30 days). Of course, there’s some sellers that game it by increasing their prices over 30 days before Prime Day.
I dont think it includes procong due to coupons though.
If a product had a minor coupon (e.g <5$) and the product was discounted to that price without coupon, it would still advertise lowest price despite it not really changing.
Prime Day is just Black Friday in July. Amazon is trying to get rid of old stock.