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.
These jugs are a disappointment. The glass itself is good quality and while dishwasher safe, I have noticed some of the lettering on the side is starting fade. The pouring spouts are useless and when pouring water and stocks etc more water ends up on the kitchen bench than anywhere else. There is no point to buying them, they aren't good for pouring and the measurement markers wear.