Early Pixar movies featured a hilarious reel of bloopers during their end credits, but the last time these outtakes were included was in Monsters Inc in 2001. The bloopers showed the animated characters forgetting lines, playing pranks, and other pretend mistakes that didn’t make the final cut. The outtakes were a beloved idea at the time, but they have since disappeared from Pixar movies, and the reason behind this is rather vague.
The first blooper reel in a Pixar movie was attached to the end credits of the studio's second animated feature, 1998's A Bug’s Life. Originally, the idea was to make its debut three years earlier, in the first Toy Story, but due to time constraints, the later release worked better for the animators. The second time bloopers appeared in a Pixar movie was with the 1999 sequel Toy Story 2. Pixar head John Lasseter, who also directed these early features, wanted to show a different side to Disney's animation output from what the audience had seen before. In an interview at the time, he said, “We picked shots and the characters from the film so that it had the feel that it was actually part of the film” (via the Las Vegas Sun).
Related: How Pixar Accidentally Deleted (& Recovered) Toy Story 2
The blooper's final appearance came in the end credits of Monsters Inc in 2001. While it has never fully been disclosed by Pixar as to why they no longer include the bloopers, it is speculated that it simply took too much time. The idea required the actors to return to the recording studio to revisit the specific scenes, and it was a lot of additional work for the animators as well. Rumor has it that Lasseter also claimed it was just an outdated practice. Either way, it's a shame that these hilarious blooper
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