This involves military thinking. There is a famous saying in China War: Shouchun is a battleground of Huaihe River. Once the Huaihe River falls, the whole south will fall, so Shouchun is very important. As for Jingzhou, if you want to lay Jingzhou, you must go south along Yizhou. Wei mainly needs to face Shu. It is not cost-effective to play Jingzhou on both sides. As long as the Shu kingdom is laid down and goes downstream, Jingzhou will be laid down, otherwise Jingzhou will not be laid down.