You’ve probably been aggravated trying to turn left on a busy road, then give up and turn right. So this might interest you. A recent study at Penn State found it might be better if we just made the majority of left turns illegal. Researchers used a bunch of algorithms to figure out the best way to keep traffic moving and prevent accidents. The simulations found that traffic would move smoother if left turns were banned at more intersections. It depends on the city you’re in and the traffic flows.  However, in general, the most efficient setups ban left turns near the middle of metropolitan areas and only allows them as you get farther away from the city center.