To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
I thought that my jaw muscles were fine, but gave this a try anyway. I was wrong. This takes effort to get up to a level where you can feel comfortable with it. I'll stick with it until I see a definite firming of my jowls.