The YouTube algorithm works for homepage recommendations by considering three key factors:
2. Performance: YouTube collects real-time data on how a video is performing. It tracks whether the viewer regularly watches content from a particular channel and observes how similar users react to the video. This includes metrics such as:
- Did the viewer click on the video?
- How long did they watch it?
- Did they like or dislike it?
- Did they click "not interested"?
- Did they scroll past it?
3. Satisfaction: Not all watch time is equal in value. To evaluate satisfaction, YouTube conducts surveys and feedback mechanisms. This helps gauge how enjoyable and satisfying a video is to the viewer.
All of these elements work together to determine which video is presented to a user on their homepage. The algorithm's goal is to provide a personalized and enjoyable experience by suggesting videos that align with the viewer's interests and preferences.
I got this info from YouTube employee "TODD" who works in the YouTube recommendations system
and I hope this will help you to understand YouTube better