Front struts damaged at shop

Took 2001Mazda MPV in to get new radiator with normal ride. Upon getting car back car ride was very rough. Took car back and they said front struts had leaks and needed to be replaced. They did notice any problem with struts the three previous times within 100 miles the car was on the rack including for the safety check. Is there something that could have happened to change the condition of the struts?