Before post-play, you had to open the episode menu and click on the next episode to play it. We didn't want to do autoplay for a long time because we were afraid people would fall asleep with Netflix playing and it would break the internet. So we included the now infamous "Are you still there?" popup a few minutes into episode 3 with no interaction with the player.
Now it is everywhere - YouTube, Hulu, HBO, etc. And people watch way more TV than they should.