What we do with 5-star rating system is completely ignore 2,3,4 stars which in a lot of ways just skew our analysis, hence ending up with a new score similar to Nps (5-star minus 1-star) / total stars
Why bother have a 5-star rating system then? Sounds like Netflix went down the right path, with thumbs up or thumbs down. People either zero it out, or give it five stars.