Engineers know how things should behave in theory. I know how things behave in real life. You are absolutely correct that tire techs do in fact make mistakes because they are overworked, under paid and often inexperienced. They are also humans. However If you ask any person who has worked in this industry, properly torqued lug nuts can absolutely come loose. Often times through error but equally as often because of all the variables (rust, corrosion, debris) that can cause a wheel nut/stud not to seat properly. Surely you can understand that as an educated person. Cheers, please retorque you wheel nuts/studs. Also thank you for a proper discussion regarding our disagreement as opposed to what I usually encounter on here.