Noot noot is the signature call of Pingu, the claymation penguin from the Swiss stop-motion children's series of the same name, where his honking voice became his most recognisable trait. Online, editors began slowing and lowering that call to create a sad version that flips its cheerful meaning, and the clip spread through meme videos, reaction edits and soundboards as shorthand for disappointment. Its appeal endures because listeners recognise the original instantly, so the gloomy twist needs no explanation.