This has really become Cartman's like thing. No matter where Cartman is, he always wants to be some place else. That's basically Cartman's M.O. through a lot of the shows. Is he just. This wasn't the way 3rd grade was. It sucked. But Cartman wants to be anywhere but where he is, and he often has a song about it. He often has a song about the place he'd rather be.
—South Park Creator Commentary on the episode Fourth Grade
This is known as an "I Want" song — a number that comes early in a musical, in which the hero(ine) expresses his/her hopes and dreams, so that we in the audience understand those dreams, and get more involved in his/her quest to achieve them.
But who cares/No big deal/I want more...
—Ariel singing Part of Your World
In almost every musical ever written, there's a place that's usually about the third song of the evening -- sometimes it's the second, sometimes it's the fourth, but it's quite early -- and the leading lady usually sits down on something; sometimes it's a tree stump in Brigadoon, sometimes it's under the pillars of Covent Garden in My Fair Lady, or it's a trash can in Little Shop of Horrors... but the leading lady sits down on something and sings about what she wants in life. And the audience falls in love with her and then roots for her to get it for the rest of the night.
—Howard Ashman, specifically referring to the above song, Waking Sleeping Beauty