Why did Germany in WW1 follow The Schlieffen Plan instead of just invading Serbia?

Question

Why did they go with the trouble of going to West instead of South at Serbia, where was war declared by Austria-Hungary?

In: Other

Answer 1

They were all allied. Austria-Hungary declared war on Serbia, who called in their ally Russia, who declared war on Austria-Hungary, who called in their ally Germany, who then declared war on Russia, who called in their ally France, who declared war on Germany. So for Germany their options were to either fight both France and Russia or to abandon their ally Austria-Hungary to fight Russia on their own. And when they had to fight both Russia and France they could either try to defend against France while trying to do like Napoleon and Charles before and invade Russia, or they could try to take France before they had mobilized and then turn around to fight Russia. The German strategy were very sound, the issue was that they were unable to execute their strategy.