The Fav-and-RT-based serotonin reward system unintentionally built into Twitter also has the side effect of forcing introverts to obsessively write pithy jokes for huge audiences for free, day in and day out. Free funny content! Sometimes by actual comedians you’ve heard of! And some of those times, from good comedians! Users don’t even have to do anything special to gain access to that, they just open Twitter and read it. Free content shoots out like a firehose.