The Emperor's New Clothes is a short tale written by Danish author Hans Christian Andersen, In the source tale, a king is hoodwinked by weavers who claim to make a suit of clothes invisible to any man not the folk ask him if he has become a naked ascetic, he realizes the deception, but the swindler has already fled.
The Naked King. Most of us know the story;. The King wished to wear the finest cloth on earth. Great weavers came. Prepared nice muslin cloth.
That's a fractured version of “the emperor has no clothes” which is related to the expression “out of the mouths of babes”. Basically, the emperor had caused such fear in his subjects that no one told him the expensive “outfit” he was “wearing” was vaporware (did not.