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 is a good product if you are intending to buy it just for selfies. Battery life is not very good. I bought it for my short videos I film using my phone. The brightness is good for a small light - it also has 3 settings. Would have loved if the battery lasted longer.