Bad "New" parts frustration.

I feel for the guys that repair cars for a living. Several friends of mine that do, have some stories to tell. One guy told me when ordering parts will ask how many do you have ? I'll need at least 2 or 3 to get one that works. He did a VW Jetta and put 3 water pumps on in 35 days.The only one that worked and didn't leak was a factory dealer part. Not to say what the car owner thought of his work..