Hello @TeamYouTube , I would like to know, why are not the thumbnails of the videos on my channel? What happens is that all my videos had thumbnails, and now they are no longer seen.pic.twitter.com/10DKNkIopT
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If you want to see it that way, yes. That's AB testing: You pick some users, and show them an alternative version of the site, and compare their interaction telemetry (how much time they spent on the page, where they clicked, etc.) with the existing users.
YouTube here wanted to try different settings for their automatic generation, so they *probably* picked .4% of the viewers, .1% as control group, and .3% using different algorithms/settings for automatic thumbnails, and measured which style caused people to want to click more.
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