Question

My product had 3.9*,got 2 5* review & became overall 4*. But now again 3.9* with same reviews. Checked last 2 review is still 5star. Why this happened?

Answer 1

This happens because Amazon’s star rating system is not a simple average—it’s a weighted average based on:

Why Your Rating Dropped from 4★ to 3.9★ Again

1. Amazon uses a rolling, weighted system

Older reviews carry less weight, and verified or helpful reviews carry more.

Even if the last two were 5★, older low-rated reviews may still outweigh them.

2. Star rating includes both public and hidden reviews

Sometimes Amazon factors in removed, pending, or unpublished reviews into the backend calculation, affecting totals.

3. Not all 5★ reviews are treated equally

Reviews marked as "Not Helpful" or unverified may carry less impact on your average.

What You Can Do

• Encourage more verified buyers to leave genuine reviews.
• Improve listing quality to prevent returns (which trigger bad reviews).
• Monitor reviews via Brand Dashboard if you're Brand Registered.