ANAHEIM, California -- Pixar Animation Studios makes magic happen, but the road to conjuring it all up is often less than magical.

Some of the masterminds behind Pixar's most beloved films, from "Toy Story" to "Up," opened up about the ups and downs of making said magic happen at Disney's D23 Expo on Saturday (August 15). Hosted by Pixar senior development executive Mary Coleman, the panel brought some of Pixar's most brilliant storytellers together -- like producer Darla K. Anderson ("Coco"), director Mark Andrews ("Brave"), director Ronnie Del Carmen ("Inside Out") and director Dan Scanlon ("Monsters University") -- for an incredible inside look into the beloved studio.

Woody was supposed to be a jerk.

This may sound crazy, but the lovable protagonist of Pixar's seminal film "Toy Story" was originally a total effing jerk. Coleman showed an early storyboard from "Toy Story," and in it, Woody was relentlessly cruel to the other toys. He called poor Slinky a "spring-wiener!" (We're kinda emotionally scarred by it, tbh.)

"We were trying to do something different and edgy, and different than any animated film," Anderson said. "We were trying to find a character with an edge... We took it way too far."

Luckily for Lasseter and the rest of the Pixar creative team, "It doesn't take much to shift the energy of a character." After a few tweaks to Woody's character to make him less of a meanie and more of a by-the-books leader, he was a whole lot more endearing -- and an incredible friend.

It's hard to imagine where Pixar would be now if their OG protagonist was more of an unbearable antagonist. "I really don't know if our studio would have survived," Coleman said.

A very special Russell and Carl scene was cut from "Up."

At some point during production, Carmen and his team needed to create a moment for Carl and Russell to bond since for the majority of their adventure, Carl had been pretty grumpy towards the boy scout. So they storyboarded an fun sequence, that was kind of like a montage, with Carl and Russell spending a day by a watering hole on their way to Paradise Falls. However, looking back at the animated scene, they decided it didn't quite make sense for Carl and Russell to have such an awesome day of fun together, knowing that the emotional gut-punch of Carl and Russell's climatic rift was coming up.

"It felt like we took their relationship to a really great place [in that scene], and after that, it would be hard to see Carl be mean to Russell again," Carmen said. "How could he do that to him? So it didn't feel right at that moment."

Remy had a whole smorgasbord of family members.

Though they were originally conceived as supporting characters in "Ratatouille," Remy's family was killed off when Andrews received a note that they added nothing to advance the overall story. "Who's the story about?" the director recalled. "Is it about Remy, or his family?"

Adding salt to our emotional wounds, he then showed us some early sketches of Remy's family -- Remy's mom was SO cute and looked like a total Mrs. Weasley, FWIW. "Sometimes, you realize that those characters are there for no reason," said Scanlon.

Dean Hardscrabble was originally a male scarer in "Monsters University."

Originally envisioned as a an overweight male monster that looked like a cross between the original film's Mr. Waternoose and Professor Slughorn, at the final hour, the character was scrapped for a female version.

Bing Bong wasn't Riley's only imaginary friend.

Gasp! Our favorite cotton candy-elephant Bing Bong was originally part of a whole bevy of imaginary friends for Riley.

"We had a lot of them," said Carmen. "One of them was Mrs. Scribbles -- she was all of Riley's drawings -- and then Corner Sun -- you know those corner suns you draw in the corner of the page? And Bing Bong was just one of them."

However, as the true message of the film became clearer for the filmmakers, so did Bing Bong's place in Riley's memories. In the film, Joy learns that childhood is fleeting and there's no better representation of that than Bing Bong. Excuse us while we go cry millions of candy tears...

"Yeti's cave" (inspired by "Monsters, Inc.") is a phrase frequently overheard at Pixar.

You know that iconic scene in Yeti's cave in "Monsters, Inc.?" Mike and Sulley had just been banished to the wastelands and their friendship was at an all-time low. That scene would go on to be notorious among the filmmakers at Pixar.

"We probably boarded this sequence at least 25 times," Anderson said. "When you consider that these sequences take weeks and months to make, that's a lot of time... for some reason, it just wasn't working."

The filmmakers went through dozens of scenarios -- "There was one sequence when Yeti was like a marriage therapist," said Anderson -- but nothing felt quite right until they eventually came up with the sequence that made the final cut.

"You guys now know," Anderson said, "that if you have something in life you just can't get right, that's your Yeti's cave."

The original opening to "Toy Story 3" was pretty boring.

"I had this brilliant idea. We open the movie where the toys are really bored," said Scanlon. "They're looking around and saying, 'Well, I guess we're not getting played with today.' That will be the joke! We'll just bore the audience right off the bat. And John was like, 'No.'"

Yeah... that didn't fly with Lasseter. Instead, the opening to "Toy Story 3" was rewritten to be the complete opposite: a rousing action sequence!

"Toy Story" almost had a creepy homage of "The Shining."

At the end of "Toy Story," toy torturer Sid gets his comeuppance when all of the toys band together to scare the heck out of him. Originally, the doll who rises out from the sandbox was supposed to say "redrum" as she crawled over to said. (As if that scene needed to be any creepier.) This was clearly an homage to Lee Unkrich's favorite film "The Shining."

So, the team had animated the sequence completely and sent it to post. But there was one major problem: Pixar hadn't cleared the rights with Warner Bros first -- and that is a HUGE no-no.

"It's one of my favorite stories. It shows our naiveté, our love of inside jokes and the other animators," said Coleman.