The last episode of Dexter, usually when people claim something is has a terrible ending I think they are overreacting, but Dexter's ending really was that bad.
Doctor Who: (either) The Curse of the Black Spot or Victory of the Daleks Sherlock: S3/Ep2 The IT Crowd: Reynholm vs Reynholm (only funny line was the pedalstool, damp squid joke, the episode itself was pretty poor)
Eastenders where they spent a whole half hour on Dot! Eastenders is not my favourite show but that episode is just engraved into my head, i cant forget it! That whole episode was just of Dot smoking and talking to herself! Complete waste of my time
The last season finale of Dexter, I was so angry.. I thought it would have ended better.. It left soo many questions unanswered. I feel like they only left it open so they could return to it years down the line. I really loved the show, and it was a huge let down.