Elite runners strike a healthy balance between focusing on inputs and outcomes during their training.
For majority of their training (80%) they focus on keeping their inputs – heart rate and perceived effort – in an optimal zone. They pay less heed to how fast they are running. Their focus is on build stamina and staying injury free.
For the rest of their training (20%) they focus on their outcome – pace. They push themselves to run harder to build speed and strength.
We control our inputs and can design habits around them. Measuring outcomes keep our habits honest. A good plan strikes a healthy balance between the two.