Movable metal type was developed in Goryeo–Joseon Korea well before Gutenberg’s printing press emerged in Europe, yet the two technologies had very different historical impacts. Gutenberg’s printing technology spread on a much larger scale, supported by economic, political, and cultural conditions that encouraged mass production and the circulation of knowledge. This contrast shows how an innovation’s influence depends not simply on being first, but on the broader environment that allows it to reach people and transform society.