When a driver pulls up to an intersection to make a right turn, they tend to stare to the left. They're just waiting for traffic to clear or the light to turn green. When it does, assuming there's no one ahead of them, they turn right without actually looking in the direction that they're turning.
Here the problem: What if someone is crossing the street? The crosswalk is right there to the right and, when the light turns green, the pedestrians get the walk signal. They can enter the street from either side. A driver who doesn't look could hit them.
Or, what if there is a runner coming through the intersection. Runners are not supposed to run with cars, but against the flow of traffic. That means that a runner going the opposite way would pass the car on the right, between the curb and the car. Again, if the driver never looks, they'll turn without seeing the runner.
This happens a lot. In one interview with the The New York Times, an experienced runner said that "about 90 percent of the time drivers taking a right turn don't bother to look right."
The problem is that drivers think only about what they're doing, knowing there is not another car in the way to the right. They don't bother to think about who they may be sharing the road with or who else might be on that side without an automobile.
This careless manner of driving is very common and very dangerous. Those who get injured in accidents may have a right to financial compensation.