It’s pretty basic when you dig into the social psychology.

A classic outside the internet experiment would be a waiting room that starts to fill with smoke. Smoke starts to leak in at the ceiling. People see it. The variable is when the confederate (word for person who is an experimenter hire) gets up and leaves. Seeing someone leave, not the smoke itself, even as it builds up in the room, is a far better predictor of human behavior in that moment. People will take this farther than you’d think, waiting and then waiting some more, until a social cue occurs.

Online is different, yes, but our social wiring doesn’t just go away. And now, the numbers of social cues are far, far easier to manipulate. I don’t know if they’re cheaper, but the numbers side of it is disturbing.