A Netflix user will browse the app for 90 seconds and leave if they find nothing.

Thumbnail artwork is actually NFLX's most effective lever to influence a viewer's choice. A user will look at one for only 1.8 seconds, so NFLX spends huge to optimize them.

Here's a breakdown🧵

1/ Spoiler alert: humans are visual animals.

Our eyes move 3-4x per second to process information and we can analyze an image in as little as 13 milliseconds.

2/ In 2014, Netflix consumer research showed that thumbnail artwork:

◻️ is "the biggest influencer...to watch content"
◻️ is the focus of 82% of browsing time

A user looks at one for only 1.8 seconds. If they can't find Netflix content in 90 seconds, they'll leave the app.

3/ Consequently, Netflix uses an elaborate thumbnail selection process for each of its 200m+ users.

The process is called aestethic visual analysis (AVA), which starts by pulling all the frames from a video.

For reference: a 1hr episode of "Stranger Things" has 86k frames.

4/ In a process known as "Frame Annotation", each frame is tagged with metadata identifying key variables:

◻️ Saliency
◻️ Frame #
◻️ Brightness / Contrast
◻️ Nudity probability
◻️ Face / skin tone