My understanding is it’s the little thrill your brain gets from the possibility of finding something super interesting. That’s the addicting piece. The gambling piece of it.

I read (or more likely heard on a podcast) about an experiment with mice and a food dispensing button. In one case, the button reliably dispensed food every time it was pressed. In the other case, sometimes the button wouldn’t work. The mice with the reliable button didn’t do anything odd. Whenever they were hungry, they would hit the button for some food. The mice with the unreliable button however would repeatedly hit the button, and they ended up being overweight.

My feeling is that if EVERYTHING on something like HN was super interesting, we’d only be here when we were up for some interesting reads. But the fact is, not everything is. But the possibility that something EXTRA interesting might pop up keeps us coming back in an addictive type of way.