Dead man's curve is a nickname for a curve in a roadway that has claimed lives because of numerous crashes. The term is in common use in the United States.

Based on this passage, why do they call it dead man's curve? Let's give stream of consciousness first:
The relevant sentence in the passage is: Dead man's curve is a nickname for a curve in a roadway that has claimed lives because of numerous crashes.
So, the final answer is a nickname for a curve in a roadway that has claimed lives because of numerous crashes.