A man can manage his calendar, his money, his reputation, and still ignore the one place everything actually starts. Decisions do not begin in the meeting room or on the jobsite; they begin in the inner world that most people never see. If that inner world is cluttered, bitter, addicted, or numb, it will eventually leak into his words, his habits, and his relationships. Solomon’s line here cuts through the distraction of performance and productivity and goes straight to the source. This scripture tells a man that guarding his heart is not a soft idea; it is the most practical leadership work he will ever do. If he neglects it, every other part of his life starts drinking from polluted springs.