Comfort and Convenience
Preferred cabin temperature differs widely, partly because clothing and whatever someone was doing beforehand change how warm they feel. A passenger arriving from a cold walk often wants less heat than the driver.
Safety and Driver Assistance
Knowing where the hazard switch, horn and gear selector sit is easier to establish before departure than during traffic. Preparation of that kind is a habit rather than a one-off check.
Multimedia and Connectivity
Hands-free calling and music playback are usually handled separately, so one may work when the other does not. If calls matter on a route, confirm the microphone path before relying on it.