Turn your god damn headlights on when it’s raining

Old cars had old-school bulbs and no sensors, so the driver, not wanting to waste bulb lifespan, was responsible for.using them when they needed them.

Modern cars with LEDs don't have the usage problem, but some cheaper models don't have sensors.

Anyway a modern car has no reason not to be have them on, unless you were parking or something and didn't want to blind people seated nearby, but that's a very specific edge case.