Ooooh! Ooh! UX guy here with an annoying ‘well acktchually!’
I read up on the research. We’re hard-wired to recognize faces and to seek them out, so there’s an unconscious attention we give to them almost against our will. That’s why paper catalogs always had smiling people wearing headsets next to the customer support number, and why we see faces in the wood paneling we’re staring at while we’re on the shitter.
The goofy expression is because they test better. The excitement and happiness is contagious even on a thumbnail, unless someone trains themselves to have a conscious disgust reaction that’s stronger than the hard-wired instinctive unconscious one. (Looks in the mirror. Looks at our team of expert haters.)
Those thumbnails are the product of millions of multi-variant tests. Every video, you can upload multiple thumbnails, see the results, and switch to the best one automatically. Knowing Russ, he’s feeling the pinch of moving to Spain and losing access to some of his bread-and-butter video topics because there’s no alt-cycling scene there, just a bunch of pro roadie try-hards, and he’s working the algo.
Not really one book, I’ve picked it up from a variety of sources over time - just digging into ‘Pareidolia’ will get you a long way with the concept. The UX part of it came from a test here, another UXer sharing a study result somewhere else… I spent ~10 years with access to dedicated research teams, fairly state-of-the-art usability labs and a budget, so I picked up a lot by osmosis there.
the zwift reddit is full of people putting them together wrong. I haven’t actually seen one in person but based on the photos they look pretty low quality
