4. The O.C.
This show had an amazing run in the first couple of seasons and after the insane third season finale where they killed off a major character, they should have utilized the final season having the rest of the characters try and work through their loss and eventually moving on. Instead what we got was a season filled with the lead almost instantly moving onto another person which wasn't even that bad, but the person he ended up with was someone the show spent almost three full seasons making us despise. They made her do a complete character change just to throw a new love interest into the show. The finale that finished off this dreadful season off with was a flash forward sequence that had the most predictable ending of all time: Them getting married. Yeah sure. No problem. Alright. WHATEVER!