Impressions funnel

Studio's analytics carries a chart called impressions and how they led to watch time. It lays the journey out in stages: how often the thumbnail was served, what share of those turned into views, and how much watch time came out of the far end.

An impression only counts when at least half the thumbnail sits on screen for longer than a second, and only on YouTube's own surfaces. A view from an embed, an external link, a notification or an ad never enters the funnel at all. That is why the view figure inside the chart is lower than the video's total, and the size of that gap tells you how much of the audience arrived from somewhere YouTube never served.