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.
Valve has split after not even a month. But I guess thats how they make money. Make parts that are poor quality and need replacing constantly. Going to buy valves from a different company in the hope they are better quality.