Keep your friends for friendship, but work with the skilled and competent.
— Robert Greene

Many highly intelligent people are poor thinkers. Many people of average intelligence are skilled thinkers. The power of a car is separate from the way the car is driven.
Edward De Bono skilled quote

Don't wait until everything is just right. It will never be perfect. There will always be challenges, obstacles and less than perfect conditions. So what. Get started now. With each step you take, you will grow stronger and stronger, more and more skilled, more and more self-confident and more and more successful.
— Mark Victor Hansen

One is rarely an impulsive innovator after the age of sixty, but one can still be a very fine orderly and inventive thinker. One rarely procreates children at that age, but one is all the more skilled at educating those who have already been procreated, and education is procreation of another kind.
— G. C. (Georg Christoph) Lichtenberg

No man was ever so completely skilled in the conduct of life, as not to receive new information from age and experience.
— Terence