Comfort and Convenience
Cabin temperature is a common point of disagreement, because people differ in build, clothing and how still they sit. What one passenger calls pleasantly cool another finds draughty, so agreeing a setting early usually helps.
Safety and Driver Assistance
Locating the essentials, such as lights, wipers, demisters and the hazard switch, while parked means you are not searching for them later. Preparation of this kind leaves fewer small decisions to be made while the car is moving.
Multimedia and Connectivity
Battery level is the usual worry on a long trip, and a passenger charging a phone is a separate matter from playing music through it. Where charging is available, sorting it before departure avoids mid-journey fumbling.