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.
I am in love. With my Roomba 690. I chose this particular model after researching all the options. Best bang for the buck, in my opinion. I’ve named him Roger; it seems everyone names their Roombas. He cleans like a champ. Don5 know what I’d do without him. Do yourself a favor and BUY a Roomba!