Take 2 people: one a talented auto mechanic, one is me (not mechanically talented). Give us both the task of changing all 4 tires on a car.
I take 8 hours. The mechanic takes 1. (Made up numbers, but you get the idea).
8 hours reflect my effort, sure. But you want the tires changed. If the mechanic finishes in 1 hour, great. That's what you're paying for — changed tires. Not hours.