Katherine Heigl says the success of 'Grey's Anatomy' gave her 'a false sense of confidence' that led to her getting 'mouthy'

• Katherine Heigl says the success of "Grey's Anatomy" emboldened her to make controversial comments about it.
• "There was no part of me that imagined a bad reaction," she told Variety.
• Heigl left the show in 2010, a year after speaking out about working long hours in harsh conditions.

It's been 13 years since Katherine Heigl's controversial "Grey's Anatomy" exit, but the discussion around her infamous comments lives on.

In a Variety "Actors on Actors" interview with her "Grey's" costar Ellen Pompeo, Heigl was upfront about how her many comments to the press got her into trouble in the 2000s.

"I was so naive. I got on my soapbox and I had some things to say, and I felt really passionate about this stuff. I felt really strongly," Heigl said. "I felt so strongly that I also got a megaphone out on my soapbox."

"There was no part of me that imagined a bad reaction. I felt really justified in how I felt about it and where I was coming from," she continued.

Heigl, who played fan-favorite Izzie Stevens on the medical drama for six seasons and won an Emmy, left the show amid controversy in 2010.

A year prior, she'd spoken out about the show's long hours and grueling working conditions.

"Our first day back was Wednesday. It was — I'm going to keep saying this because I hope it embarrasses them — a 17-hour day, which I think is cruel and mean," Heigl told David Letterman in a 2009 episode of "The Late Show With David Letterman."

This wasn't the first time her comments about the show made headlines. In 2008, she gave an infamous Vanity Fair interview in which she called her "Grey's" character arc a "ratings ploy" and described her hit film "Knocked Up" as "a little sexist."

The same year, she withdrew her name from Emmys consideration, saying she didn't feel she was given the material to warrant a nomination, a statement that reportedly offended "Grey's" creator Shonda Rhimes.

Heigl told Variety the success of "Grey's" emboldened her to speak out at the time.

"I think that gave me this confidence that was a false sense of confidence. It was rooted in something that couldn't and maybe wouldn't always last for me," Heigl said. "So then I started getting real mouthy, because I did have a lot to say, and there were certain boundaries and things that I was not OK with being crossed."

Heigl admitted that the backlash to her comments was gutting.

She said she "felt such shame for such a long time, and then had to go, 'Wait. Who am I listening to? I'm not even listening to myself. I know who I am.'"