Lose bolts/nuts after picking up the car......

To anyone with a car, had anyone experienced the left wheel bolts or nuts not tightened after picking up the car from a dealership servicing or any repairs? My colleague and I took our cars to the dealership for a normal service plan, and both cars, in the same October month had wheels not tightened, I could use my fingers to un***** them. Unfortunately, her wheel spanned out while driving whereas mine broke one bolt/nut then I took it in.

different workshops, and different car brands, loose bolts/nuts after picking up the car - we didn't plan it but only know it after our accidents.