My wife used to leave the headlights on some of the time when she left our 2003 Merc Sable. Then the lights would run the battery down to nothing.
Now my Chevy Aveo LT 2011 Turns OFF the headlamps (all lighting) as soon as the key is turned off and removed (within one second). Amazing IMPROVEMENT from my point of view.
One less thing to worry about.
Lg