Use a Video’s Slider to Find the Most Watched Parts
You probably already know that you can use the slider right below a video to go to any part you want. However, the slider has another useful feature.
You’ll notice there are a few white spikes right above the slider. These spikes represent the most watched sections of every video. If you’re looking for the most important part of the video, all you need to do is hold the slider and move it to the left or the right of the video.
But don’t worry; you won’t have to focus on these spikes. When you reach the most watched section, YouTube will let you know with a Most Played message right on top of the video.