Our anticipation for Disney's first major 2021 release, Raya and the Last Dragon, has been mounting since the animated film was first announced. Originally set to debut during Thanksgiving 2020, Raya is at last available to see in theaters or order on Disney+ with premiere access March 5.Back when the project was announced during the summer of 2019, Cassie Steele had been tapped as the voice of Raya. But a year later, it appears Kelly Marie Tran took on that role. So, why did Cassie Steele leave Raya and the Last Dragon?Why did Cassie Steele leave 'Raya and the Last Dragon'?According to Raya and the Last Dragon producer Osnat Shurer, the character of Raya went through some changes since the initial announcement of casting Cassie, which is why Disney had to find another voice to lend to the character. \n\n"There was a key change to Raya's character," Osnat told Cinema Blend. "The original [voice actress], of course she's wonderful, and she was a perfect fit for Raya's character then, and then the character changed a lot, and so it was necessary to shift voice.""Kelly just embodies Raya," she continued. "The character shifted and then it shifted even more, as that work together started to happen between the voice and the writer, the animators and it takes on a whole different life. It's just one of those creative change moments."While they didn't go deeper in depth about the specifics of Raya's changes, or why Kelly became a better fit, it's rather easy to understand from a marketing perspective. To quote Atom Tickets, "with the utmost respect for the talented [Cassie], [Kelly] is an upgrade ... After the vicious backlash she received from less enlightened corners of the internet for her portrayal of the plucky, earnest Rose Tico in Star Wars: The Last Jedi, fans have rallied around [Kelly] as an actress and she's quickly become a fan favorite."In the words of Osnat, there's "a wit, a warmth, a strength, and then, a vulnerability that still had power behind it, that all combine together" in Kellys' performance. "She's a producer's dream," she continued. \n\nAnd according to directors Don Hall and Carlos López Estrada, they knew Kelly was perfect as soon as they wrapped the first recording session."She is Raya — just her buoyancy and her positivity, but yet there's a strength as well to Kelly and the character," Don told EW. \n\nWhat's more, it sounds like her improvisational ad-lib skills were what really impressed the team at Disney. "We had this little dramatic moment; it was written as a few lines," Carlos said. "And I remember her going, 'Hey, I have some ideas because this is normally how I would say this or I have some questions. Do you mind if I tried it a little bit differently?'""She went for it, improvised for a minute, and had us all in tears," Carlos continued. "We changed the scene and reblocked the animation so that it would follow what Kelly did that day because she just clicked on something that was so much bigger than anything we had imagined." \n\nWe can't wait to see her bring Disney's newest princess to life.