Why didn't germans invade france through switzerland in ww1?

During both World War I and World War II, the Swiss Confederation managed to keep a stance of armed neutrality, and was not involved militarily. However, precisely because of its neutral status, Switzerland was of considerable interest to all parties involved, as the scene for diplomacy, espionage, commerce, and as a safe haven for refugees.

Water(like when there is a hurricane)some foods(not enough for everyone)