[nitrogen]

I just go left to right, top to bottom

I doubt this is how most people's eyes actually scan a visual field. I expect there's a lot more randomness going on subconsciously, and that face-like features cause a higher subconscious dwell time.

had to click on something quickly...but that's not how Youtube works.

I think for most people it is. Scroll scroll scroll tap, all within a few seconds.

[jjk166]

It's how we scan text. I'm also reading the titles of the videos. Maybe there's a very quick scan of the page beforehand, but if I click on any of the options presented, it's only after I've done that main scan.

When you're only presented with a tiny bit of information, it doesn't take long to evaluate a decision. A few seconds is a long time. No one, at least to my knowledge, is opening youtube and clicking on the first thing they see in milliseconds. Hell, just variation in page loading time probably has a bigger effect on what we see first. Critically though, there's no deadline - even if you see something you want to watch quickly, you don't have to click on something if you don't see something you want to watch. Without time pressure, there's no need to make an impulsive click.