“I can guarantee that if you manage to start a habit and keep sticking to it, there will be days when you feel like quitting. When you start a business, there will be days when you don't feel like showing up. When you're at the gym, there will be sets that you don't feel like finishing. When it's time to write, there will be days that you don't feel like typing. But stepping up when it's annoying or painful or draining to do so, that's what makes the difference between a professional and an amateur.”