3. The Office (2005-2013)
What Was So Bad? The Office USA didn't just have a bad pilot, it had a bad first season. The opener is clunky and has way too much exposition, the writers make the mistake of trying to introduce us to all the characters at once and haven't really gotten the hang of the mockumentary format yet (the actors either play it too much like single-camera or play up to the cameras completely). Michael Scott is a complete creep in season 1 with his Gordon Gecko slicked back hair and sloppy dress, he's like the creepy boss who always comes on to you at a Christmas party and shows no signs of what he later became - the genuinely likeable worker who got promoted out of his ability and is trying desperately to pretend he knows what he's doing.
How Did They Fix It? The show was also still in the shadow of its UK counterpart, and frankly this only harmed it. A lot of Season 1 scripts are re-workings or adaptations of the UK episodes, and thus much of the content doesn't play well on the other side of the pond. As strange as it sounds, the UK version was just a little too acerbic for American tastes and it wasn't really until Season 2 that the sweeter side of The Office was brought out and we got to see more of the inter-personal relationships and get to love the characters. The rivalry between Jim and Dwight was also amped up more and brought a lot more humour to the show that didn't necessarily focus on Michael, meaning B-Plots could be utilised a lot better.