In Germany, if the authorities notice a significant number of accidents on a certain portion of roadway, they call in an engineer to fix the problem. They redesign the curve, they re-grade the road, whatever it takes.
In the US, if the authorities notice a significant number of accidents on a certain portion of roadway, they start issuing lots of traffic tickets on that portion of the road, and it becomes a steady source of revenue for the city.
That answer is a bit pat, of course, but there is a kernel of truth to it: Americans and Germans have different attitudes. That includes different attitudes about driving, but it also includes different attitudes about design and engineering. The US has a culture of the Rugged Individualist: we make the road however we make it, and as the driver it’s your responsibility to drive safely. It’s your fault if there’s a crash. Germany has a culture that it is the responsibility of the engineer to think carefully about the project, anticipate how things can go wrong, and create a design that is logical, consistent, and makes sense in everyday use.