Which show had the worst ending?

Many shows, especially teens dramas, have a very bad habit of making an undeniably excellent series and then screwing up the ending. My question is what show screwed up the whole series with the last season? Game of thrones is NOT an option I think we are still healing from that.

Mine is still Gossip Girl. Sorry, I understand if he was Joe on that show then absolutely he could’ve been everywhere seeing everything all at once but Gossip Girl’s reveal make me downright angry to this day.