(photo is the earliest known photo of the Boston Marathon, 1904)Running a marathon is a lot about not giving up, putting one foot in front of the other, listening to what you're telling yourself, keeping going, keeping going long after you think your body is out of gas ("the wall"), keeping going even when your quads are screaming at you to walk, and your brain is bargaining with you (those people over there are walking why can't you?, no one is making you do this race, just walk for goodness sake and be done with it). It's about holding your focus, taking the next step and finishing the race.
Writing is like that too. It too is a lot about not giving up, putting down the next paragraph (or sentence, or word), listening to what you're telling yourself, keeping going, keeping going long after you think you're out of ideas, keeping going even when the committee in your head is screaming at you to stop, telling you it's not good or funny or interesting or anything and would you just put down your pen already. It's about holding your focus, writing the next thing and finishing the race.
The best races are the ones you thought you could never finish. And the best ideas often take the longest to discover. (At least that's my story and I'm sticking to it.) Perhaps Bill Bowerman (1911-1999), legendary track and field coach and Nike Co-Founder, said it best:— “Sometimes what matters is not what dog is in the fight but how much fight is in the dog.”