Because a longer traffic jam propagates through the entire road network, possibly blocking earlier exits, making the entire network less efficient. I am German

Because a longer traffic jam propagates through the entire road network, possibly blocking earlier exits, making the entire network less efficient. I am German and can confirm that the zipper rule is holy here, but people often have problems following it, especially unexperienced drivers afraid of merging. Very often, there are additional signs to remind drivers of the rule [1][2][3]. [1] https://www.schilder-versand.com/assets/gfx/product/300x300/hinweistafel-rei%C3%9Fverschluss-variante-2-13925.jpg https://www.schilder-versand.com/assets/gfx/product/300x300/... [2] https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Hinweiszeichen_23c.svg/800px-Hinweiszeichen_23c.svg.png https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Hi... [3] https://www.schilder-versand.com/assets/gfx/product/300x300/hinweistafel-rei%C3%9Fverschluss-variante-1-13924.jpg https://www.schilder-versand.com/assets/gfx/product/300x300/...