You cannot concentrate more, you can only concentrate less. You cannot try harder, you can only try less.
In other words, trying to concentrate more, or “trying harder,” actually distracts us from our natural ability to simply be in the moment and do it. In this sense, concentrating more equates to concentrating less and trying harder is equivalent to trying to try.
The Need To Win
When an archer is shooting for nothing he has all his skill. If he shoots for a brass buckle he is already nervous. If he shoots for a prize of gold he goes blind or sees two targets— he is out of his mind!
His skill has not changed. But the prize divides him. He cares. He thinks more of winning than of shooting— and the need to win drains him of power.
~Thomas Merton, The Way of Chuang Tzu