Comfort and Convenience
Preferred cabin temperature is a good example: some people set it once and forget it, while others adjust constantly. Clothing, time of day and personal tolerance all differ, so one setting rarely suits every occupant.
Safety and Driver Assistance
Spending a minute locating lights, wipers and mirror adjustment before setting off means fewer searches later. Learning these positions while parked turns them into habits, so they can be used without pausing to hunt for them.
Multimedia and Connectivity
Keeping a phone charged on longer trips is a separate need from playing music or taking calls. If a suitable power outlet is available, a short cable and a fixed place to rest the phone help.