Gotta agree about Roseanne. The ending was so notorious it became famous, and when I heard of it I was glad I hardly ever watched that show. Talk about stabbing the loyal viewers in the back!
One ending not included on the list which was super creepy was Quantum Leap, which I did watch loyally the entire time it was on, joined in write-in campaigns not to cancel it and to have it air at the preferred time, and heck, I even helped raise money for Dean Stockwell's star on the Hollywood Walk of Fame and attended the first convention! Then what should happen but the creator, Don Bellisario, got his knickers in a twist over the show being cancelled and wrote an ending to insult the network which probably made no impression on them as they have no heart, soul, or brain, but really hurt the viewers! At least he got the chance for a final episode! There were shows such as The Partridge Family, The Brady Bunch, and others among my favorites which were cancelled over the summer so never got to film a special ending, and a guest star or new cast member got the last line of the entire series!
1993, the year Quantum Leap was cancelled, saw the cancellation of The Wonder Years and everything else of quality on network TV, and there has been very little worth watching since. Can you tell I am still not over it?