Each of us has a different purpose. Regardless of what it is, it drives us to be disciplined. This is because we will do what is necessary to fulfill it. But, where does purpose come from? I believe purpose is found in life experiences.
While these are not all the forms of purpose, these have helped me build and maintain discipline.
Devotion - Whether it is your significant other, your family, your country, or yourself, you have a purpose to enrich the lives of those you love - be it physically, socially, emotionally, financially, and spiritually. In particular, your family likely made many sacrifices to give you a better life than they had. Give them ten fold what they gave to you.
Injustice - You cannot change the injustices in the world if you do not first change the man in the mirror.
Adversity - When you find yourself in a situation that makes you uncomfortable, what will you do? Tolerate the pain or push yourself to escape it? This video explains the power of adversity very well.
Passion - When you thoroughly enjoy what you are doing, you will do whatever it takes to do it. Passion is in the heart. The mind can be persuaded but the heart cannot
What is your purpose?