How well did Glee end? Fans were clearly delighted. I didn't see it, but I did watch the finale of Newhart, which was ingenious.
Dexter rightfully deserves to be dead last in this list. Just hacking off the last 3 minutes alone would helped a lot.
Redditor ChallengeResponse compared IMDb ratings of the first and last episodes of famous television shows to see whether they were relatively good or bad, as well as compared finales with average ratings for the respective durations of each show. You can see all of the charts here.
Do any of these rating shifts surprise you?
-via Twisted Sifter