Glee premiered in 2009 and changed the television landscape. Its mix of heart, teen drama, and music turned it into an overnight sensation, as did its diverse cast of chaotic characters. Indeed, Glee's ensemble included numerous students and teachers with great voices but inconsistent characterizations.
The main characters in the show didn't always make the best choices; in fact, they arguably always made the worst possible ones, leading to some of the show's most questionable storylines. Still, fans kept rooting for them, even when they made mistake after mistake without necessarily learning from them.
Emma Kissing Finn
Emma Pillsbury was one of the most likable characters in Glee. Sweet, wholesome, and loyal, Emma spent years harboring a secret crush on Will Schuester, eventually getting together with him after several obstacles, including a failed engagement and a failed marriage.
In season 4, Finn takes over the Glee Club while Schuester is away and begins to bond with Emma. He kisses her in a moment of confusion, and she freezes in shock. The kiss derails Finn's friendship with Will and threatens Emma and Will's engagement. It's also a terrible storyline, considering Finn is supposedly nineteen while Emma is in her thirties.
Schuester Leaving For Carmel
And speaking of Will Schuester, the original Spanish teacher and coach of the New Directions leaves McKinley between seasons 5 and 6 for a high-paying job at Carmel High. However, he proves deeply unprepared to coach the notoriously competitive Vocal Adrenaline, and he eventually returns to McKinley.
Schuester was never a good fit for Vocal Adrenaline. His teacher-who-wants-to-befriend-his-students vibe is all wrong for Carmel High, and the kids in VA don't care for his friendship; all they want is to win. Fortunately, Will understands it and returns to the New Directions, where his saccharine brand shines the most.
Sue Going Against The Glee Club
For all intents and purposes, Sue Sylvester is Glee's de-facto antagonist. One of the most competitive characters in television, Sue is the coach of the Cheerios, hellbent on destroying the New Directions. She spends most of the show trying to ruin them, except for a brief stint where she acts as co-director alongside Schuester.
This period is arguably the best for New Directions, leading them to a win at Nationals. It also proves that Sue was wrong to go against the New Directions when she could've easily been their ally. Sue loves to win, and leading the school underdogs to victory would've further cemented her legacy of victories. Her not seeing this is a glaring mistake.
Sam Going To New York
Sam is the most unambitious of all the characters in Glee, but there's nothing wrong with that. He never dreams of fame or success; instead, he just wants to be happy. He briefly entertains the idea of becoming a male model and even travels to New York to pursue this goal.
However, Sam realizes the city's lifestyle isn't for him, and he goes back to Lima. He secures a job as an assistant football coach at McKinley, finally content with his life choices. Sam only goes to New York because all his friends are there, but never likes the idea of living there. At least he tries it, though.
Artie Having Unprotected Sex
Sarcastic and sassy Artie is the nerd of the Glee Club. An aspiring filmmaker, Artie also goes to New York to attend the Brooklyn Film Academy, where he becomes something of a ladies' man. In one of Glee's most cringeworthy storylines, Artie begins having regular unprotected sex with two girls, eventually catching chlamydia.
Artie's choice to have casual sex is fine, but him not telling the girls isn't. Furthermore, unprotected sex can lead to worse STDs than chlamydia or even unwanted pregnancies, something Artie clearly doesn't consider. Luckily, he understands his mistake and vows not to repeat it.
Santana & Brittany Filming Themselves
Santana and Brittany are one of the best couples in Glee. On paper, they don't make much sense; Brittany is sweet and oblivious, while Santana is a complete savage. However, they are perfect together, bringing out the best in each other. Santana has trouble deciding what she wants to do and even suggests not going to college, but Brittany concocts a plan to change her mind that involves making a sex tape.
The idea is fitting for a ditz like Brittany, but it also causes serious problems for them in the future. Santana later confesses that the tape keeps haunting her, and she deeply regrets making it. Worst of all, the plan doesn't even work because Santana drops out of college anyway.
Blaine Cheating On Kurt
Arguably the most beloved couple in Glee, Blaine and Kurt have a very chaotic relationship. Blaine is too needy, clingy, and insecure, while Kurt is overtly selfish and somewhat resents Blaine. The two hurt each other several times, but Blaine does the worst possible thing when he cheats on Kurt in season 3.
Blaine's betrayal leads to the first of several breakups, sinking him into a deep depression. He eventually recovers and even harbors a crush on Sam, another unpopular story that led nowhere. Blaine's cheating brings him considerable pain, and he states numerous times how much he regrets his mistake.
Kurt Breaking Up With Blaine (The Second Time)
Kurt has undeniable talent and flair to spare. He is a genuine star who loves the stage and the drama that comes with it. However, Kurt often takes the drama into his real life, making too much out of a small thing. His relationship with Blaine is the perfect example, as he dislikes many of Blaine's traits but blows them out of proportion.
Their differences eventually become unbearable, and Kurt ends his engagement with Blaine. He regrets the choice eventually and tries to get back together, only to find out Blaine is now in a relationship with Karofsky. Kurt's decision to break up never made much sense, and fans continue asking why he did it.
Finn ing The Army
Like Sam, Finn isn't particularly ambitious and doesn't know what he wants to do -- for example, he briefly entertains the idea of becoming an actor, but he gets rejected from the Actor's Studio. Finn eventually decides to the Army, much to Rachel's distress.
However, Finn only s because he doesn't know what else to do. His heart isn't in it, leading him to accidentally shoot himself through the thigh and get "semi-dishonorably discharged." Finn does discover his true calling as a teacher, further confirming that his brief stint in the army was a mistake.
Rachel Quitting Broadway
Rachel's choice to quit Broadway has aged like milk. The ambitious starlet never hit her Broadway dreams and worked hard to get into the school after fumbling her initial auditions. She then secured the role of Fanny Brice in the Funny Girl revival, finally fulfilling her life-long dream.
However, she gets tired of the show after only a few months and quits to go to LA and shoot a TV pilot. The decision comes out of nowhere and makes no sense, considering everything fans knew about her character. It also backfires because the pilot stinks, and Rachel becomes persona non grata in both Hollywood and Broadway, forcing her to return to Lima with her tail between her legs.