Principles are ways of successfully dealing with reality to get what you want out of life.
Ray Dalio, one of the world’s most successful investors and entrepreneurs, cites principles as his key to success.
You need to push through and that requires self-discipline to follow your script. It's important to remember the connections between your tasks and the goals that they are meant to achieve. When you feel yourself losing sight of that, stop and ask yourself "why?" Lose sight of the why and you will surely lose sight of your goals.