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.
This was my 3rd order of this product. Obviously if I didn't like it, I wouldn't keep coming back for more. It is a good product, but seems a little pricey. I mix it with another cereal (50-50) and that extends it and brings the overall cost down.