Your attitude and thoughts affect you, your life and the people around you. The thoughts that you think most often affect your behavior and expectations, and the manner people treat you. If you worry too much, lack faith in yourself, and often run movies about problems and failure in your mind, you will eventually attract problems and failure, and would make your life difficult. Being negative, you will feel that you do not deserve success, and would therefore not try to improve your life.

From Visualize and Achieve