Comfort and Convenience
Seating position is the clearest example. Height, leg length and posture habits mean two people rarely agree on the same setting, and a driver who mainly commutes short distances may prioritise differently than one covering long routes.
Safety and Driver Assistance
Sorting out lights, mirrors and demisting before setting off is simply preparation. Doing it while stationary means fewer unfamiliar movements later, which matters most in a car you have only recently begun driving.
Multimedia and Connectivity
Phone use splits into separate needs. Keeping a battery topped up over a long day is one question; whether calls can be handled without holding the handset is another, and each depends on what a given setup supports.