How did Zhuge Liang analyze Liu Biao's situation in Jingzhou?

Zhuge Liang analyzed the situation of Cao and Sun, and then analyzed the situation of Liu Biao and Zhang in Jingzhou:

"Jingzhou is a strategic hub extending in all directions, with Hanshui River in the north, South China Sea in the south, Wu Hui in the east and Bashu in the west. It is a good place to use force. It's a pity that the present Jingzhou master has no ability to keep it. This is probably what God specially left for the general. Don't you want it, general? "