Blinkers are funny that way. People seem to somehow leave them on to confuse us other drivers, or they choose not to use them at all ... feast or famine.
But blinkers are also a serious think. According to accident statistics, there were 6.5 million automobile accidents in 2009, resulting in 3.5 million injuries and nearly 40,000 deaths. And one of the top for causes cited was "failure to signal when turning and/or changing lanes."
Again, I'm an old-school dude, and when I took Drivers' Education we were force-fed a concept called defensive driving. The objective of driving, according to our rules of war, was survival and you fought the battles by looking at all other drivers as potential foes. Driving meant following the rules but watching your "enemies" for erratic behavior and clues to their intent. One big clue was turn signals.
I live in a state that for some reason has a warren of interconnecting one-way streets at the heart of every urban downtown area ... I've heard the "lady" the gives me my turn-by-turn GPS directions give up and start swearing. Add this to the growing complexity of the highway systems and the bob-and-weave drivers who feel the need to add 25 or 30 mph to any posted speed limit, and you see the danger of people not employing the most basic, most helpful of driving aids ... again, the turn signal.
POINT OF RANT: The light blinks on your dashboard and makes a sound ... turn the damn thing OFF!!