Staying on the treadmill is one thing, and I do think it’s related to staying true to our commitments even when we’re not comfortable. But getting back on the treadmill the next day, eager to try again, is in my view even more reflective of grit. Because when you don’t come back the next day — when you permanently turn your back on a commitment — your effort plummets to zero. As a consequence, your skills stop improving, and at the same time, you stop producing anything with whatever skills you have.
This backs up the idea that we keep failing until we succeed and that those that quit won’t succeed because they stop long before they reach the point they can succeed.
From Grit by Angela Duckworth