The Big Bang Theory is one of the most successful sitcoms in TV history. The show has a cult-following after 12 seasons of beloved characters and unique storylines. The show also made the seven main characters stars in their own right, earning millions of dollars. However, every success story has its criticisms and controversies.

RELATED: The Big Bang Theory: 10 Reasons Why Bernadette Got Worse & Worse

Due to TBBT revolving around "geek" culture, many stereotypes were built into the show that many of its viewers didn't appreciate. And the bigger and brighter the stars became, the more things were said and spun in the wrong way. Keep scrolling to see 10 controversies that could have killed The Big Bang Theory.

Kaley & Johnny Dated IRL

Actors Kaley Cuoco and Johnny Galecki portrayed one of TV's famous couples, Penny and Leonard. These two were best friends who were destined to be together, despite their obvious differences. They two had chemistry on screen, which really sold the storylines and it's clear to see why.

Kaley and Johnny actually dated for two years while filming the show, but didn't tell a soul about their relationship in fear of ruining it for anyone. If media outlets realized they were dating in real life, rumors could have killed their relationship and the show. The pair didn't want to kill the magic between Penny and Leonard, thus keeping their relationship on the DL.

Other Countries Tried Duplicating The Series

The Big Bang Theory was such a success that a team in Belarus tried duplicating the series. They called the show The Theorists and it was the spitting image of The Big Bang Theory. The actors were, of course, different but the characters were similar.

RELATED: The Big Bang Theory: 10 Reasons The Gang And Stuart Aren't Real Friends

Chuck Lorre and Warner Brothers went after the Belarus show warned them about copyright infringement before pursuing legal action. The show overseas was unlicensed, which was a red flag for many of its actors and they quit on the spot.

Its Spin On Nerd Culture Was Offputting

One of The Big Bang Theory's biggest criticisms was how the show encouraged stereotypes. The show was based around "nerds" who weren't as attractive as the other guys but were incredibly smart and had good jobs. Due to their "poor" looks, they had trouble getting girls but were excited by comic books, Star Wars, and Star Trek.

The basis of the show perpetuated that those who were bright and interested in comic book fandom couldn't get girls and were lonely and pathetic with health issues like asthma and lactose intolerance. The show was a global success, but there were plenty of haters who were happy to see it off TV.

How Much Money Is Too Much Money?

The gang reads letters from Howard's father

Once the show was off the ground running, it became a massive success. With each new season, the main cast (Kaley Cuoco, Johnny Galecki, Jim Parsons, Kunal Nayyar, and Simon Helberg) earned more and more money. Eventually, they were earning a staggering $1 million an episode a piece! But what about the actresses who portrayed Bernadette and Amy?

RELATED: The Big Bang Theory: 10 Most Hated Storylines

By this time, they were also main characters but earning around $200,000 an episode. Once word got out about the inequality in pay, the main characters did what was right and took a pay decrease so that Melissa Rauch (Bernadette) and Mayim Bialik could get a raise.

12 Seasons Equates To Lazy Writing And Going Through The Motions

The guys hanging out at the comic book store in The Big Bang Theory.

Another criticism haters and fans had of the show was the direction the show was taking in later seasons. Many believed that 12 seasons was far too long for the show to run and that the writers got lazy.

They set Raj up in yet another arranged marriage, Penny didn't want children but hey, she's a woman on TV so they gave her a surprise pregnancy, and the actors appeared to be going through the motions. Storylines were no longer exciting or unique, they ended quickly without a real outcome.

Mayim Bialik's Op-Ed Piece On Women In Hollywood Was Controversial

At the height of the Harvey Weinstein allegations, Mayim Bialik (Amy) came out with an op-ed piece for The New York Times about being a woman in Hollywood. While her intentions were good, many fans of the show had issues with her remarks on being a woman and how to represent as a woman.

More importantly, she claims she had different experiences in Hollywood because of the way she dressed as opposed to other women in the industry. "I have decided that my sexual self is best reserved for private situations with those I am most intimate with. I dress modestly," she said. "I don’t act flirtatiously with men as a policy."

And Bialik's Views On Parenting

Big Bang Theory - Mayim Bialik as Amy

Mayim isn't the only actor on the show who had controversial remarks over the course of her time on The Big Bang Theory but they were enough to get all walks of life talking. As a mother of two children, Mayim made her parenting techniques clear and shared with fans how she chose to parent. This included being an anti-vaxxer for her children, which caused an uproar from fans.

She expressed her appreciation for those concerned for her children but claimed that she and her ex-husband did what they did after thorough their own research and help from doctors.

Penny Didn't Need To Be A Mother

Penny and Leonard lie in bed and talk on TBBT

One criticism that haunts many viewers today was the writers' choice to give Penny and Leonard a baby. Penny and Leonard had serious conversations about parenthood but seemed fine with not conceiving. By by the 12th season, Penny found out she was pregnant.

The problem viewers had with this is that not every woman needs to have a child. Women don't always need to become mothers and there's nothing wrong with that. Most women become mothers on sitcoms and it was refreshing for Penny to be satisfied with her life sans children. But clearly those in the writers' room had different thoughts.

There Was A Soft Kitty Lawsuit

Whenever Sheldon is sick, he makes whoever is around him sing "Soft Kitty" to him. It's a short song that his mother used to sing to him as a child and it still soothes him as an adult. After 12 seasons, the song stuck and fans loved singing along. However, there was actually a copyright lawsuit because of this since TBBT never had permission to use the song.

The original song came from 19th century Poland and is titled "Wlazł kotek na płotek." In 2015, the creator's daughters filed a lawsuit against Warner Brothers for stealing the song and the lawsuit dragged on for a couple of years!

Sexism Was Subtly On The Forefront

Even diehard fans can't deny that Sheldon and Howard could be sexist. Sheldon claims he doesn't know any better but he slut-shamed Penny for years — even after she married Leonard! He talked about women only wanting salads and gossiping and let's not get started on Howard's misogyny.

He was incredibly invasive and forceful on women without their consent. Howard's gross behavior got better after he married Bernadette but his past still lingered.

NEXT:  The Big Bang Theory: The 10 Best Sheldon Cooper Quotes