It also means, most importantly, that when a customer clicks on the “Add to cart” button, the sale goes to that seller. This seller is called the “winner” of the Buy Box and will make far more sales than any other seller for that product, usually greater than 90% for new, non-media items. The seller in the Seller Managers are not usually permanently there, and the Seller Managers-winning seller can change every 15-60 minutes, sometimes resulting in a new winner, sometimes resulting in the same winner as before. These rotations are hidden from a customer already viewing the page, as Amazon uses cookies to ensure each customer sees only one Buy Box winner per hour. However, if the Buy Box winner’s metrics changes for whatever reason, such as the price of the product or the amount of available stock, or the overall Performance of the seller according to Seller Performance criteria, then Amazon may display rotation to another seller before the one-hour time period is up. Think of it like a Ferris wheel:

In this analogy, each passenger car represents a seller’s product offer toward that product listing – each car has the potential to carry a person (each offer can make sales). However, only one car at any given time is in the correct position (the Seller Managers) to let passengers on easily. Amazon has an operator (algorithm) which selects which car is in this position based on contributing factors like Fulfillment Method, Price, Seller Performance Metrics, etc. If there are ten perfectly equal sellers all competing for the same product Buy Box, they would get roughly 10% each. This means that each seller will have their offer shown in the Buy Box for roughly 10% percent of each day. Alternatively, a relatively high performing seller could have 70% of the Buy Box, an average seller could have 25%, and a lower performing seller, 5%. Therefore, instead of saying that a seller wins or loses the Buy Box, a more correct term would be to say that a particular seller has a lesser or greater share of the Seller Managers.