How to make the best of both strong and weak–that is a question involving the proper use of ground.
The secret of winning is to use everyone, playing to their strengths rather than forcing them to put forward only their weaknesses.
Hence those who are not good fighters may be found more useful behind the lines, for example if they can run well then they may carry messages. If they are intelligent, they can process information. If they lack all skill then perhaps they can just carry things for you.
It is a mark of leadership to be able to identify strengths and weaknesses and then play to the person’s strength.
In business, the ‘Peter Principle’ is that people get promoted to their level of incompetence and then remain there. In war even more than in business, this is a losing approach.