The sudden inexplicable inability to demonstrate an action to an audience specifically summoned to view said action.

This phenomenon receives its name from the premise of a pet "talking" parrot who is suddenly silent when guests are invited to see it "talk." "I swear!," says the owner, "He says all kinds of stuff! He says 'hello', he says our names! Really! I don't know why he won't do it now...." while the guests nod and say, "Suuure, he talks. We totally believe you."

When you eat dirt for the first time and leave your family to build a shack in the woods