You know....
You put your life into someone else's hands when they work on your vehicle.
Business knows no ethics. Techs are trying to log as many hours as they can and do not really care about you or your expensive vehicle. Next time you are at a shop watch how the "tech" test drives customers cars(sometimes to lunch and other personal errands). I am sure they don't drive their own vehicles that way because they had to pay for them(and the tires and fuel). Using a hidden gps unit can go a long way. Loose wheels, broken/missing parts, and even sabatoged vehicles are not uncommon.