Not sure what happened....??!

Thursday I was out running errands in my car and heard an awful loud noise under my car. Got it checked out and 2 brackets had broken off the left muffler. The weird thing is the brackets didn't line up the way they were when the guy went to weld/repair the brackets. He ended up having to cut approx a half inch off of the h-pipe to get everything to line up correctly. Any thoughts as to what could have caused the breakage? And NO I didn't take the car 4 wheelin or anything...lol.

probably was under stress when it broke, dunno...

Did it get backed into anything by mistake? I don't know why he had to cut the H pipe. You have about 2" or more of play to slide the mid pipes forward and back.