TV finales, generally speaking, fall into three broad categories: happy, tragic, or ambiguous. There's a time and a place for each of those, but television shows have a long, sad history of fluffing their lines at the last minute.
Bringing the curtain down on the right note is a tricky undertaking, not least because the audience has usually invested a vast amount of time in the series, gotten to know some of the characters as intimately as their closest friends, and spent many a pub session explaining their predictions for the final season to anyone who will listen.
Why so many shows drop the ball when it comes to their endgame is a mystery to rival the plot of Lost, but there are occasions when it feels like the showrunners did it on purpose; times when they seemingly crafted a conclusion to get the fans riled up, possibly in retaliation to the abuse they were subjected to throughout the show's run.
From last-minute character deaths, to rendering everything that came before a dream, these are the cheap tricks that stick in the fans' minds for all the wrong reasons.