I came across this image the other day. I think it applies well to the founder journey too - many people focus too much of their attention on what the competition is doing, when in reality I've found it's much more effective to focus on how you can best serve people, and solve their problems.
The athlete mindset still has its place - revenue doesn't lie; it's objective. But I've come to the belief that thinking too much in these terms and not focusing on the craft of building is counter-productive, especially in the early days.
Be an artist when building.