There are few occasions in popular entertainment that are more promising, or more perilous, than the finale of a great television series. When done well, it provides resolution and closure. We understand that the characters have accomplished worthwhile things and built solid relationships but still have fresh opportunities before them — a new romance, a new child, a new job. We’ve welcomed the characters into our living room, as the cliche goes, for years, and there’s a particular mix of nostalgia involved in seeing even a one-sided relationship end happily. The same sentimental sigh accompanies the closing of a beloved novel.

Conversely, a dud of a finale sours the entire series. It gives the impression that you and the people behind the show had very different ideas about what it was about, what made the characters likable, and where you wanted them to end up. You feel cheated, as if you could have been doing something more productive with all of those 30- or 60-minute chunks of your life. A lot’s at stake.