Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
Great razor - bought for my girlfriend as she wasn't happy with her existing one. Found it was a close shave but also smoother after shaving. It has gel pools on the razor head that helped with irritation. Definitely said she would recommend!