Collins goes on to explain, “The 20-mile march is more than a philosophy. It’s about having concrete, clear, intelligent, and rigorously pursued performance mechanisms that keep you on track. The 20-mile march creates two types of self-imposed discomfort: (1) the discomfort of unwavering commitment to high performance in difficult conditions, and (2) the discomfort of holding back in good conditions.” This practice is particularly important for leaders.