Comfort and Convenience
How upright a person likes to sit is largely personal. Leg length, arm reach and habits built up over years of driving all differ, which is why two people rarely settle on the same position.
Safety and Driver Assistance
Weather rarely waits. Knowing in advance how to clear a misted screen or change the lights means those actions come from memory instead of guesswork when conditions change part-way through a journey.
Multimedia and Connectivity
A call arriving mid-journey is easier to handle if the phone has been set up beforehand rather than left in a bag. Music and charging are separate matters, each depending on the facilities available.