A television show's pilot episode is, arguably, the most important one of all, since this is when audiences decide whether or not to spend a lot of time with these people and the situations that they find themselves in. Sometimes, a show is so good right from the beginning and starts to falter once a few seasons are underway. Other times, a pilot is dull and not indicative of the rest of the show, and it only improves from there.

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Which pilots are worth praising... and which ones make it tough to want to watch the rest of the series? Here are some of the greatest (and worst) pilots in TV history.

Best: New Girl

new-girl

The New Girl pilot is one of the best because it introduces the characters, the loft, and the show's sense of humor. Jess Day (Zooey Deschanel) moves in with three guys: Coach (Damon Wayans Jr.), Nick (Jake Johnson), and Schmidt (Max Greenfield).

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Sure, it's true that Coach is gone and replaced by Winston (Lamorne Morris) as early as the second episode. But the pilot still proves what the show is about: a girl trying to recover from a breakup and find herself while becoming good friends with a group of guys. It's nothing like she would have expected, and it makes for a hilarious and quirky sitcom that lasted for six great seasons.

Worst: Pretty Little Liars

pretty little liars A

If fans of Pretty Little Liars go back and watch the pilot, they would definitely agree that the show changed a whole lot from that original episode. It's ultimately about four girls -- Hanna Marin (Ashley Benson), Emily Fields (Shay Mitchell), Aria Montgomery (Lucy Hale), and Spencer Hastings (Troian Bellisario) -- who look into the disappearance of their best friend, Alison DiLaurentis (Sascha Pieterse).

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The pilot focuses on a funeral for Ali and introduces dramatic plot points for each of the four main characters. PLL ultimately becomes a show about many mysterious storylines and red herrings, and there isn't that much of a mysterious feeling in the pilot. It even seems like the girls wonder if a dead Ali is texting them when they get texts from "A." It's not the best episode of the show, and it's not one of the best pilots out there.

Best: YOU

With a show like YOU, if the pilot was bad, it would be impossible to want to keep watching. Since it's about a stalker named Joe Goldberg (Penn Badgley) who can't stop watching the lovely Guinevere Beck (Elizabeth Lail), the very first episode had to be strong enough to help viewers get past the obvious creep factor.

The pilot is a thing of TV beauty. It's got many voice-overs from Joe which are actually good, it sets up the first meeting between the two characters in the bookstore where Joe works, and it ends on a dramatic note that proves that Joe is super dangerous and even violent.

Worst: Life In Pieces

Husband and wife embrace in Life In Pieces

Life In Pieces won't be returning after its fourth season finishes airing, which is sad news, since it's a funny and all-too-real look at being part of a family that is pretty unconventional (which is every family, of course). Although the sitcom is totally hilarious, the pilot really isn't. It's not a fair look at how quirky and sweet the Short family are.

The pilot features lame storylines like Colleen (Angelique Cabral) and Matt (Thomas Sadoski) getting intimate in a car and the dad and grandpa John (James Brolin) having a funeral while he's still around. The episode is awkward and seems to be trying too hard.

Best: Grey's Anatomy

Eliza Minnick has a chat with Arizona when the two were seeing each other

Yes, it's true that many former fans of Grey's Anatomy don't watch the show anymore and haven't for years, as many feel the quality is much lower these days. But it's also true that this Shonda Rhimes-created show has one of the best pilots.

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In the first episode, Meredith Grey (Ellen Pompeo) and Derek Shepherd (Patrick Dempsey) meet at a bar and spend the night together, meeting once again at the hospital. Fans were surprised to learn that he was a doctor at the very same hospital where she was an intern. The pilot also introduces the characters that fans love (and miss) the most, from Cristina Yang (Sandra Oh) to George O'Malley (T.R. Knight). It's solid.

Worst: The Good Wife

The Good Wife

The problem with the pilot of The Good Wife is that it doesn't feel like the rest of the show. Yes, it does set up the main storyline -- Alicia Florrick (Julianna Margulies) starts working at a law firm now that her politician husband has embarrassed her with his scandal -- but that's about all that it does.

The Good Wife's strength lies in the fascinating cases in every episode, but also in the slightly odd characters who populate the law firm (and who hire the lawyers for their expertise). The pilot is honestly nothing to write home about and Alicia doesn't feel that strong-willed or brilliant yet. The rest of the show, however, is amazing.

Best: Lost

Evangeline Lily as Kate and Matthew Fox as Jack in Lost

The Lost pilot is definitely one of the best TV pilots ever. The first show is infamous by now: Jack Shepard (Matthew Fox) wakes up in a forest and sees trees and sky above him. He quickly realizes that he and his fellow passengers have been in an awful plane crash and they're now stranded on an island.

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The pilot succeeds on two levels: it starts developing many character arcs as viewers learn more about each of the major players, and it also sets up the mysterious tone of the island and the show in general. It's visually stunning and also just really interesting.

Worst: Parks And Recreation

Parks And Recreation is such a wonderful sitcom, and it lasted for seven awesome seasons. Many fans say that people should start watching from the second or even third season, however, because they just don't feel that the early episodes hold up.

On that note, the pilot is one of the worst, very different from everything the show would become. At the beginning of the show, Leslie Knope (Amy Poehler) is more annoying than endearing and she's not as loveable as she is later on. The tone feels off and it's just not that funny.

Best: Gilmore Girls

Lorelai grinning at Luke and asking for coffee on Gilmore Girls

The Gilmore Girls pilot is honestly flawless. Sure, there are some dated fashion and hairstyles, but fans don't care about that when they can see the world of Stars Hollow unfold for the very first time. In this first outing of the popular show, fans watch Lorelai Gilmore (Lauren Graham) working at an inn and getting her sweet daughter Rory (Alexis Bledel) ready to go to a fancy prep school called Chilton.

Everything that fans adore about this show is present in the pilot: the beautiful town, the townspeople, Luke and his diner, Lorelai and Rory drinking lots of coffee, and the sharp wit that the mother/daughter duo always share.

Worst: Seinfeld

Jerry, George, Elaine, adn Kramer watching tv in Seinfeld

Seinfeld is one of the best sitcoms ever, which is why it's such a shame that the pilot is one of the worst.

The whole first season is really weak compared to the rest of the show (although the last two seasons aren't considered to be amazing, either). The pilot features Jerry Seinfeld wondering if a woman wanting to sleep at his apartment means that she wants to date him. It's not as funny as many of the other episodes and the pilot isn't quoted as often as the more famous Seinfeld moments are (like "The Puffy Shirt" and "No soup for you").

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