The Big Bang Theory is still one of the most popular sitcoms of all time. The showrunners were ready to keep on making more seasons, which is why fans were shocked to learn that TBBT was coming to an end after only twelve seasons. More than 18 million people tuned in to see The Big Bang Theory's series finale, and they were not disappointed.

The writers managed to wrap up the series with a heartfelt finale that both fans and the cast loved. But was this grand finale what the showrunner envisioned from the beginning?

Well, Steve Molaro finally revealed that coming up with this finale was no easy task.

They had to alter many of the characters' storylines throughout the final season to give fans this happy ending.

The Big Bang Theory Came To An Unexpected End After Jim Parsons Decided To Leave the Show

Jim Parsons decided to quit The Big Bang Theory after filming for season 11. His reasoning actually made sense. At that point in his career, Parsons was too busy, between filming TBBT, narrating the spin-off series Young Sheldon, and starring in other movies, he was running thin.

Additionally, Parsons had a sort of awakening following the tragic loss of his 14-year-old dog. The actor suddenly realized that he was only six years younger than his father was when he died and realized that he didn't want to keep playing Sheldon Cooper any longer. "If you told me that, like my father, I had six years left to live," he told USA Today, "I think there's other things I need to try and do."

Following Parsons' announcement that he was leaving The Big Bang Theory, showrunners, Chuck Lorre and Steven Molaro, briefly considered continuing the series without Sheldon Cooper. Ultimately, they decided against it, choosing to wrap the series after twelve seasons.

"I couldn't wrap my head around the idea of going on without the whole ensemble — and the whole ensemble is why we succeeded," Lorre told The Hollywood Reporter. "In pulling it apart and re-approaching it as a fraction of what it was just never felt right to me. I've seen other shows try and fail to take a character out of their realm and carry on."

Writing The Big Bang Theory Series Finale Wasn't Easy For The Showrunners, And It Didn't Go As Planned

The Big Bang Theory succeeded in doing something many other shows fail at: creating the perfect ending to the series.

Fans and the cast alike loved the series finale of TBBT. However, one of the showrunners revealed that writing the final episode of the series was extremely challenging.

"This episode gave us all a lot of sleepless nights," Molaro told Deadline in 2019. "A lot of that pressure came from ourselves and really wanting to stick the landing. I think our approach emerged from a lot of conversations that began early this year when we knew this would be the final season."

He continues, "That gave us time to plan and we ended up landing on [the tactic of emphasizing] what the feeling of the finale was going to be and not really trying a big, final "The End" stamp on it.

We knew the audience was saying goodbye to these characters, but that these characters didn't need to be saying goodbye to each other."

Steve Holland, another one of the writers for TBBT, revealed that the finale fans got is not what they had originally envisioned.

"We had been talking about this finale for a long time and certainly, it's the episode that we thought about more than any other episode. So certainly there were things earlier in the year that changed," he told Deadline. "I'd say it was more a case that those things evolved into an ultimately better version of those ideas. I don't think anything really fell out.

"

Ultimately, it's clear they did a great job wrapping up the show.

How Does The Big Bang Theory Cast Feel About the Series Finale?

Fans loved the series finale of The Big Bang Theory, and so did the cast. In fact, the final table read was one of the most emotional moments for the entire cast and, over the years, they have opened up about what they thought of the finale.

For instance, Kunal Nayyar revealed that he thought it was "a beautiful way to end" things, explaining that he didn't have any objections to the script when he finally read it.

Kaley Cuoco also admitted she loved the way things ended in TBBT. The actress who portrayed Penny was especially blown away by Sheldon's Nobel Prize speech, praising Jim Parsons' performance.

For his part, Parsons revealed that he couldn't have been more satisfied with the series finale. "It ended in the way that I hoped it would in that it felt right," he told Entertainment Tonight.

"There were probably a million different ways it could feel right. I would talk with some of the writers and I know as they were writing it they were nervous. I said, 'It's the finale, you can't get it completely right. Someone's gonna hate it.' But I don't think that was actually the case with this, which was really sweet. I think it wrapped up in the right way."