Stainless Overmount

I heard that you should not install a stainless steel sink in granite counters overmount, why?
as there is no reason why can imagine. the only question that could be cut and the (self-rimming) overmount sink is larger than one would be one color and the room as the cut is lower .. But once inside, I think they have the same integrity. Why would a steel concern, not a porcelain sink is beyond me.