Netflix elaborates on this in their blog post: https://about.netflix.com/en/news/new-top-10-on-netflix https://about.netflix.com/en/news/new-top-10-on-netflix

Netflix elaborates on this in their blog post: https://about.netflix.com/en/news/new-top-10-on-netflix https://about.netflix.com/en/news/new-top-10-on-netflix > Figuring out how best to measure success in streaming is hard, and there’s no one perfect metric. Traditional measures like box office or share of audience (which was designed to help advertisers understand success on linear TV) aren’t relevant to most streamers, including Netflix. Having looked at the different options, we believe engagement as measured by hours viewed is a strong indicator of a title’s popularity, as well as overall member satisfaction, which is important for retention in subscription services. In addition, hours viewed mirrors the way third parties measure popularity, encompasses rewatch (a strong sign of member joy) and can be consistently measured across different companies. Years ago, Netflix got a lot of flak for using "users who saw atleast 5 minutes of a series" as an indication people watched it. Quantifying video performance based on watch time has become more industry standard (especially on social media which loves autoplaying videos) as it accounts for retention.