This is my favorite Bruce Lee quote of all time. It is the success recipe for any goal you are trying to achieve.
"The will to win. The attitude 'that you can win if you want to badly enough' means that the will to win is constant and no amount of punishment, no amount of effort, or no condition is too 'tough' to take in order to win.
Such an attitude can be developed only if winning is closely tied to the practitioner’s ideals and dreams. Experience shows that an athlete who forces himself to the limit, can keep going as long as necessary. It means that ordinary effort will not tap or release the tremendous store of reserve power latent in the human body.
Extraordinary effort, highly emotionalized conditions, or a true determination to win at all costs will release this extra energy. Therefore an athlete is actually as tired as he feels, and if he is determined to win he can keep on almost indefinitely in order to achieve his objective."
There is no weapon deadlier, to ANY opponent you face in life, than your will to win.