You must be as joyful when you fail again and again as you are joyful when you succeed. It is often when you fail that you move toward the goal without being aware of it. You must feel joy even when you have not fully succeeded but only moved toward achievement of your goal.
B.K.S. IyengarWhenever asana is done mechanically from the front brain, the action is felt only on the peripheral body, and there is no inner sensation, there is no luminous inner light. If the asana is done with continual reference to the back of the brain, there is a reaction to each action, and there is sensitivity. Then life is not only dynamic, but it is also electrified with life force.
B.K.S. Iyengar