Meet Resistance
Pressfield gives a name to the force that stops people from writing the book, starting the business or beginning the training plan. He calls it Resistance.
Resistance is invisible, comes from within and never sleeps. It shows up as procrastination, distraction, self-doubt and endless rationalising. It strikes hardest just before you finish something important.
Pressfield lists the kinds of activity that most often trigger it: creative work of any kind, starting a business, a new diet or health plan, education, and any act that requires commitment to long-term growth over short-term comfort.