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.
Edit..to my previous review. very good beans provided you use in within 10 days. gets stale very quickly even you store in air tight vacuum seal containers. And yes they are more oily than normal. Try small batches before ordering a kilo.