If you are driving well and have to listen to someone in the back seat instructing you to speed up, slow down, change lanes, turn here, et cetera, it can be annoying. If you are living in surrender to the Spirit of Jesus, it will be costly to your flesh. However much of your flesh (the old man) is still around will be making lots of noise when you obey the King.
Requiring your flesh to be silent about how much something costs or about serving someone who has abused you or anything else that requires death to your flesh will prevent you from derailing in your obedience. Allowing that old man to continue to make noise in the back seat can distract you. The Holy Spirit fruit (Galatians 5:22-23) will give you power to throw the old man out of the car.