This is how car parts are put to the challenge

All assembled car parts undergo real torture: the doors get closed 30,000 times, seat cushions and backrests get brushed 20,000 times and each control button gets pressed 5,000 times. These are some examples of the most severe tests that a car has to pass before its future owner takes possession. Most of these tests are carried out when the model is still a prototype. Others are performed on all production cars, immediately before they leave the factory. The goal is to guarantee the quality and reliability of the parts as well as of the car as a whole.