For most of YouTube’s history, the most important ranking factor was views. Get enough people to click the play button and watch your video climb in search ranking.
Over time, the net result of this was a diminished user experience, promoting silly things like click-bait cleavage thumbnails and gaming the system by purchasing views from overseas click farms.
More importantly, it pushed genuinely good and helpful videos down in the rankings.
2012 Algorithm Change
In 2012, YouTube made a significant change to the ranking algorithm by emphasizing the metric of “watch time” as a key ranking factor. This change looks at the following:
- How long viewers watch a video
- How much “site watch time” a video encouraged OR How often and for how long a video bring people to YouTube and keeps them there