The intent was to create border friction, pressure Qian State, and simultaneously compel them to deploy more troops to the borderlands.
But it's one thing to go out and stir up trouble; you can get away with that. But you stirred things up so much you got yourself routed, beaten soundly, and came back thoroughly thrashed by them.
Were you trying to pressure the Qian people or boost their confidence?
Indeed, Zheng Fan's past exploits had given them excessive self-confidence. It's true that Qian State's military readiness is lax, and it's also true that Qian soldiers don't hold up well in a fight, but even a broken ship has a few good nails left.
