Courtesy is the lubricant of social interaction (or was that vodka, I’m not sure?); without it we would have chaos at every turn, humans being the avaricious, narcissistic, aggressive species that we are.
Much of what we define as courtesy comes from early parental education on social conventions, e.g. holding the door for a lady, or helping a blind person across the street. There are some times however, when courtesy can be downright dangerous, and at others, outright deadly.
Driving a car is a complex mental and physical activity that relies heavily on being able to interpret various “signals” almost instantaneously and in parallel. Coming to a stop-sign for example, the driver has to immediately interpret pedestrian traffic, road conditions (slippery, etc.), visibility (can I see around that bush?), and most importantly, other cars in the same intersection and their “intent”. With respect to this latter point, a clear signal of intent from the other driver, within the context of the rules of the road, is crucial.
For example, coming to a 4-way stop at the exact same moment as another car requires first, that you (and he/she) know the rule that the car on the right has the right-of-way, and secondly, that you assert that right-of-way decisively. This assertiveness sends a clear signal of your intent to the other driver.
Yet, time and time again I see misguided folks who, in the name of courtesy, wait for the other driver to cross even though they have the right-of-way. The other person doesn’t quite know what to do, so he waits for some kind of sign from the “courteous” driver. The supposedly courteous guy finally decides, “Well since he doesn’t want to take advantage of my kindness, I guess I’ll drive through”, just at the same moment as the other guy decides, “This fool doesn’t know what he’s doing”, and also starts to cross the intersection. Crash.
I remember very vividly a deadly scenario a few years back on our 3-lane main street. An elderly lady was trying to cross the median at a point that has no stop sign or crosswalk. The driver of a panel van in the left-hand lane stopped in mid-run to let her cross. She interpreted his courtesy as an all-clear, and as she passed in front of his van into the middle lane, another car hit her full-blast and sent her flying to her death.
We are social animals; everything we do sends a message to others.