The world is a distracting place. No matter where you are or what you're doing, there are any number of things designed specifically to draw your attention elsewhere. It's true when you're driving, too, which is why automakers like BMW have crafted technologies like lane departure warning.
Of course, even if we can all admit to arriving at a destination without being able to remember a single salient detail about how we actually got there, or vibrating the car across a set of rumble strips every now and then, it takes a talented marketing department to get the message across in a manner we'll actually understand.
Scroll down for a video showing one man's aimless head doing everything but driving. But beware, this one is a wee bit *warning–NSFW–warning* due to a brief scene at a clothing-optional beach. Sorry, was that distracting?