Car crashes are actually the perfect example, because car fatalities aren't just a function of engineering a safe and sturdy car, and human inattention both can't be eliminated, but also isn't independent of design.

For instance, how many people ride in the car? What is the average car trip length? Why and when are people driving? Speed profiles, line of site in both car and environment. Does traffic all flow one way, can a car ever land in incoming traffic if it loses control, are traffic barriers designed to bring an out of control car safely to rest with good line of sight to the accident? Are features keeping drivers alert or distracting them?

The difference between lots of fender benders with a bit of panel beating and constant fatalities can come down to multiple causes, many outside of engineering a safe car.