16 stars who walked away from their successful TV shows

In February, America Ferrera, who is the lead on and executive producer of NBC's "Superstore," announced she'd be leaving the show after its fifth season.

"The last five years on 'Superstore' have been some of the most rewarding, enriching and enjoyable years of my career," the actress said in a statement obtained by CNN. "Producing, directing and acting with this wonderful cast and crew has given me opportunities to grow as a person and storyteller. I'm so grateful to my partners at NBC and Universal Television for the support and belief they have always placed in the show, and I'm most thankful to the brilliant Justin Spitzer for creating the funny, smart and relevant world of 'Superstore' and inviting me to be a part of it."

The actress played Amy on the show — and "Superstore" has already been renewed for a sixth season.

Justin Chambers first began playing Alex Karev on the medical drama in 2005, and he's one of few cast members who's remained on the show since its first season.

"There's no good time to say goodbye to a show and character that's defined so much of my life for the past 15 years," Chambers said in a statement obtained by The Wrap. "For some time now, however, I have hoped to diversify my acting roles and career choices. And, as I turn 50 and am blessed with my remarkable, supportive wife and five wonderful children, now is that time."

According to TV Line, his last episode aired in November, though fans did not know at the time that would be the final time they'd see Karev.

That said, Chambers did a voiceover a few episodes later in what was his character's official farewell — and many fans called it the worst goodbye a character on "Grey's" has ever had.

Skeet Ulrich, who played F.P. Jones on "Riverdale" for multiple seasons, announced he was leaving The CW show earlier this year.

According to Comicbook.com, in an Instagram live video, Ulrich said he decided to leave the show because he "got bored creatively."

"Riverdale" creator Roberto Aguirre-Sacasa told Entertainment Weekly that he's still leaving room for Ulrich to potentially return to the show.

In December 2019, long-time "Jersey Shore" star Nicole "Snooki" Polizzi announced she was "retiring" from the MTV reality show, reported Us Weekly.

"OK, you guys, I love you so much, and don't hate me for my decision, but I have to do what's best for me at the moment, and I am retiring from 'Jersey Shore,'" she said on her podcast,"It's Happening With Snooki & Joey," which she hosts with her friend Joey Camasta.

"I am not coming back to [the show] for a season four, if there is one. And there's a lot of reasons why, but the main reason is really … I'm just like, I just can't do it anymore," she added.

The reality star went on to say that she has tried to quit the show many times and that she really wants to spend more time with her three kids and husband, Jionni LaValle.

"Jersey Shore" first aired in 2009 and Polizzi has starred on a number of the series' spinoffs including "Jersey Shore: Family Vacation" and "Snooki & JWoww."

After playing Dr. Lawrence Kutner on "House" for two seasons, actor Kal Penn temporarily left Hollywood for the White House.

When Penn became an associate director for the Obama administration's Office of Public Liaison, his character on "House" was killed off.

"The Big Bang Theory" star Jim Parsons decided that after 12 seasons it was time for him to say goodbye to Sheldon Cooper and the CBS sitcom.

Even a deal that would have reportedly nabbed the actor more than $50 million over two years couldn't convince the actor to stay.

In a lengthy and heartfelt post on Instagram, Parsons thanked everyone involved with the show, as well as the fans. "I will miss all of you and all of this more than I can say and more than I can know at this time," he wrote.

After his departure was announced, CBS decided it would end "The Big Bang Theory" after 12 seasons, too.

After three seasons of drama, Mischa Barton was tired of playing Marissa Cooper.

After her character's death, the actress told "Access Hollywood," "My character has been through so, so much and there's really nothing more left for her to do."

Later, Barton admitted that she wasn't having a very good time on the show.

"I think I just got to the point where I was like, 'I'm not sure I'm enjoying this anymore,'" she said in a segment taped for "Dancing With the Stars" in 2016.

Christopher Meloni decided it was time to turn in his badge and leave Detective Elliot Stabler behind after salary negotiations hit a wall, according to The New York Times.

After five seasons of playing Dr. George O'Malley on "Grey's Anatomy," T.R. Knight made the decision to leave medical drama at the peak of the show's popularity.

In 2009, the actor told Entertainment Weekly that he experienced a "breakdown in communication" with show creator Shonda Rhimes and was upset to see his character receive less screen time.

Dave Chappelle left his own successful sketch-comedy show after three seasons.

"And I think that that was a irreconcilable moment for me," he said in a 2017 interview with "CBS This Morning." "That I was in this very successful place, but the emotional content of it didn't feel anything like what I imagined success should feel like. It just didn't feel right."

When Adam Brody was cast as Seth Cohen on "The O.C" it meant leaving behind a recurring role on "Gilmore Girls" as Lane Kim's boyfriend Dave Rygalski.

When Brody left, his character's departure was explained by having Dave leave for college in California.

David Caruso famously walked away from cop drama "NYPD Blue" after salary negotiations went sour.

According to Entertainment Weekly, Caruso was reportedly asking for $100,000 per episode, which was more than double the $40,000 per episode salary he received for season one.

In 2018, Topher Grace told Indiewire that after portraying Eric Forman for seven seasons he was financially stable enough to leave the show.

"For me, five or six years ago, I looked around at my life and I had just met the woman who is now my wife. I was feeling really confident and good, and it occurred to me that I was really lucky to have been on a sitcom for a lot of years. I realized then that I didn't really need a lot more money," he told the publication in 2018.

"Gilmore Girls" proved to be a great stepping stone for Jared Padalecki, who left the series after five seasons when he landed a lead role on "Supernatural."

The actor's exit from "Gilmore Girls" was quick and he was happy to get some "closure" when he made a cameo on the series reboot.

After nine seasons of playing a fictionalized version of himself, Jerry Seinfeld walked away from his NBC sitcom.

"I wanted to end the show on the same kind of peak we've been doing it on for years," he told The New York Times in 1997. "I wanted the end to be from a point of strength. I wanted the end to be graceful."

After playing Dr. Cristina Yang for 10 seasons, Sandra Oh said goodbye to "Grey's Anatomy."

In a later interview with Vulture she explained that she "felt like I did all I wanted to do."

"I didn't feel like, 'Ugh, that's all I can do, I've done everything.' It was more than that. It was actually, dare I say it, a sense of satisfaction," she added.

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