When you’ve been driving a while, you don’t need the speedometer any more. Maybe you check it when you start to drive in a congested area or pass by a cop. But, you know what 40 feels like, and you know when you’re supposed to drive 40. But we tend to become comfortable with going over the limit.
Calories are the same. They’re a good reference that you should check from time to time… But if you spend all your time focusing on them, you won’t get to enjoy the road along the way.