By this understanding, the gradual introduction of email was arguably one of history’s greatest feats of mass Skinneresque conditioning. We might imagine those first offices wired in the 1970s and 1980s as so many Skinner Boxes, ourselves as the hungry pigeons. By the 1990s, we would all learned to peck, or check email, in hope of a reward. And once created, that habit would not only open us up to all sorts of commercial possibilities, including various other Internet applications depending on the almighty power of check-in to regularly collect human attention.

Tim Wu, The Attention Merchants, loc. 656