Finally, the answer has been revealed for the question we've all been asking since "Grey's Anatomy" epic and emotional season finale - Why did Derek Shepherd have to die?

During the 2015 Summer TCA press tour in Beverly Hills, Calif. on Tuesday, show creator Shonda Rhimes opened up about her decision to kill off Patrick Dempsey's character - and it was for a good reason.

Rhimes told critics that killing Dr. Shepherd, a brain surgeon nicknamed McDreamy, was not an easy decision but said it was the only way to preserve his love for Meredith, his wife and mother to his children.

Ellen Pompeo played Dempsey's love interest for 11 seasons on the ABC long-running medical soap.

"The decision to have the character die the way that he did was not a difficult one in the sense of what were the options?" Rhimes said, according to Us Weekly. "Either Derek was going to walk out on Meredith [Ellen Pompeo], and leave her high and dry, and what was that going to mean? That was going to suggest that the love was not true, the thing we had said for 11 years was a lie and McDreamy wasn't McDreamy. For me, that was untenable."

In an episode titled "How to Save a Life," Shepherd was hospitalized after being involved in a serious car accident and later died at a hospital other than Grey Sloan Memorial when doctors failed to properly diagnose the extent of his injuries.

"Meredith and Derek's love had to remain Meredith and Derek's love," Rhimes continued. "As painful as it was for me as a storyteller, because I had never really thought that was going to happen, it preserved what felt true to me, was that Derek was going to have to die in order for that love to remain honest. Because I really couldn't have the idea that he just turned out to be a bad guy who walked out on his wife and kids be a true story. To me, it felt like that was the only way to make Meredith and Derek's magic remain true and forever frozen in time."

Dempsey's exit from the show was shocking since the actor still had one year left before his contract ended. However, Rhimes revealed that the decision was mutual.

"We had a lot of discussions about it," Rhimes said. "It wasn't easy or fun, it is never easy or fun. We've been working really hard for a long time together. We're family. Those choices and those decisions are never easy for any of us."

As for losing her TV husband, Pompeo called it an interesting challenge creatively because "as an actor, those are the best scenes to play. That's the meatiest stuff. As difficult as it is, we have something really juicy."

"It was great, wasn't it? It was great to see 'Grey's Anatomy' so relevant and taking the national conversation in its 11th season," ABC president Paul Lee said of Derek's tragic exit. "It was a difficult decision. Patrick obviously has lots of interests outside. He's very big into motosport. Shonda decided that was the way to go."

Rhimes teased that season 12 will be "lighter in tone." She was joined on the panel by "Scandal's" Kerry Washington and "How to Get Away with Murder" star Viola Davis.

"Grey's" new season will premiere on Sept. 24 at 8 p.m. EDT.