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.
Although I bought this shoes one size up, it fit very very tight. No room for my extra spacing. Recommend buying 2 size up. Even 3 sizing up is no problem. Rather wear bit large than small. It does hurt my toes. I might just go back and wear crocs. Cheaper, more space for toes.