I think it is because of Zen, most people in Japan don't actively practice Zen anymore but the influence is still there. Think of the tea ceremony, Bonsai trees

I think it is because of Zen, most people in Japan don't actively practice Zen anymore but the influence is still there. Think of the tea ceremony, Bonsai trees, sword making etc, everything should be perfect, clean, minimalism that is how one reaches Satori, the Japanese are very self conscious. Same principles of zen applied to the modern world.