Comfort and Convenience
Preferred cabin temperature is a good example: some people want steady warmth, others cooler air moving constantly. Height, clothing and plain personal taste all differ, so a setting one passenger finds pleasant can feel wrong to another.
Safety and Driver Assistance
Spending a minute before setting off, checking where the lights, wipers and hazard switch sit, means those functions are already known when they are needed, rather than being learned while the car is moving.
Multimedia and Connectivity
Keeping a phone charged during a long drive is its own need, separate from calls or music. Where charging is available in a cabin, the practical value is arriving with a usable battery rather than a flat one.