In Willy Wonka and the Chocolate Factory (the 1971 musical), each of the children was removed from the competition by them not being able to resist their character flaws.
Augustus is sucked through a chocolate extraction pipe system and sent to the Fudge Room, having fallen into a chocolate river from which he was trying to drink. Violet transforms into a giant blueberry after trying an experimental piece of Three-Course-Dinner Gum. Veruca is rejected as a "bad egg" and falls down a garbage chute in the Chocolate Golden Egg Sorting Room. Mike is shrunken to only a few inches in height after being transmitted by "Wonkavision", a broadcasting technology that can send objects through television instead of pictures.
What did the fizzy lifting drink represent to Charlie?