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.
Love it. Have been using it twice daily for 6 months, only charged once. Skin feels softer and cleaner after use. Completely waterproof so can be used in showers, very convenient. More suitable with a foaming cleanser. I'm now a big fan of Foreo, also ordered the UFO and the Iris eye massager yesterday. Will review those later.