Comfort and Convenience
Cabin temperature is a common point of disagreement, since passengers sitting in direct sunlight feel warmer than those in shade, and each person's idea of comfortable differs anyway.
Safety and Driver Assistance
A few minutes spent in a stationary car, locating the mirror, lighting and demister controls by touch, turns unfamiliar switches into routine ones before the first junction arrives.
Multimedia and Connectivity
Hands-free calling and music playback place different demands on a system: calls depend on a clear microphone path, while listening rests mainly on how the audio source is fed in.