You have staff at work and you want him to perform a lot better than what he is currently doing, then you can use a simple method that always works.
Give him a feeling of importance. Talk to him in a way that makes him appreciated and make known to him that you trust him to perform his job to the best of his ability. And then increase his responsibility.
Giving your subordinates a feeling of importance can pay dividends. Often people under-perform from lack of motivation which in turns stems from a feeling of hopelessness. They feel their work is not appreciated and they are not important.
Dale Carnegie once said that all of us are born with the words" I am important' printed on our foreheads. Use this need to feel important to your advantage