Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
My kids were so excited for these but unfortunately the balls didn’t fit into the side holes on my foosball table. I assumed all foosballs were standard size so my fault for not looking at the size. But the balls look great and we still use them by throwing the balls on the table instead.