The phrase plays on the well known expression of disbelief, replacing the final swear with duck to create a censored, more shareable version. Short reaction clips like this spread through meme pages, chat stickers in audio form, and short form video edits where a one second response is easier than typing an explanation. It stays popular because it signals total confusion instantly, works without context, and can be reused for fails, plot twists, weird news, and unexpected endings without needing the original scene or speaker to be recognised.