Motivation, that critical ingredient to success both in and out of sports. It's the one element that will allow you to get back up after repeated failures and still achieve your goals. It is not just up to you to motivate your athletes. They must have some spark of motivation themselves. As a coach you have to help your athletes develop that direction.
Good motivators are good sales people.
You have to sell your athletes on hard work and the pursuit of excellence. You have to get them to buy that their sacrifices and sweat are worth the price of the goal. This means that you have to explain to them the necessity of their efforts. Simply telling an athlete to do something is nowhere near as effective as explaining to them how this exercise or drill will help them get closer to where they want to go. Even professional athletes need outside motivation from their coach.