Comfort and Convenience
Seating position is the clearest example: height, reach to the wheel and how upright someone likes to sit all depend on build and habit. Two drivers sharing a car rarely settle on the same arrangement.
Safety and Driver Assistance
Before setting off somewhere unfamiliar, it is worth locating the lights, wipers, demister and hazard switch while stationary. Knowing where they are keeps a sudden change in weather or light from turning into a search.
Multimedia and Connectivity
Keeping a phone charged on longer journeys is a common need, since navigation apps drain a battery quickly. If a suitable power outlet sits within reach of the driver's seat, a cable can stay tidy rather than stretched across the cabin.