All the rain we've had this spring has really helped me notice how many drivers do not turn on their car's headlights in bad weather. During some of the heavy rain and spray kicked up by tractor trailer rigs, it's almost impossible to see vehicles if their headlights are off. It just shows how absent minded many drivers are. They think headlights are only for seeing but they are also for being seen. And before you say, "well you saw the cars didn't you?" Yeah. I saw them but it was tough. During an emergency maneuver, other car and truck drivers may not see them.
I always turn on my car's headlights in all weather because several respected studies have shown that accidents are reduced if headlights are used all the time. It's a good habit I carried over from my motorcycle riding days.
Volvo has the right idea in having its car's headlights and taillights turn on automatically when the car is started. I realize that most new cars have daytime "running lights" that come on automatically, but the taillights do not turn on. You need those taillights too.
My brother works for an international company that requires all employees to turn on the headlights when using company vehicles. After the policy was enforced, the number of accidents was reduced.
So remember, be seen and be safe. What do you think?