Deficiencies in the vehicle

At VOX they brought a topic which had surprised me. They had the police dressed the trucks searched for faults. One case was an Actros with Multenkipperauflieger (I believe). Defects: Danger and defective tires of the trailer had frame cracks SP had expired brake effect uneven and so on Now my question. Why do entrepreneurs drive around with such trains when they are too geizonous or broke? Why are there drivers who control such scraps? Must one be unemployed if such jobs would be such I’d rather stay more job-seekers than drive a train like that. What’s your opinion and experience?