5) The Office (U.S)
You shouldn’t, but it’s hard to resist comparing the original British The Office and its US counterpart. While Ricky Gervais’ creation was perfectly formed at a tiny 14 episodes, the version that starred Steve Carrell ran on to an enormous 201 episodes.
While the first six seasons were some of the best TV comedy out there, the show lost a lot of its greatness when the tentpoles of the series started to change. Once Jim and Pam got together, for example, the ‘will-they-won’t-they’ element that had driven the show disappeared. Likewise, when Carell stepped down from the role of Michael Scott, it lost the linchpin that was holding it together.
To be fair to The Office, it had a good ending, as it wrapped up various plot threads and character arcs when it finally concluded after nine seasons. It just wasn’t the show it used to be.