Why can black guys in general sing better then whites continuued?

this question was removed, which was stupid. Please Be adult about this people and stop being racist, im a white guy and proud. but IN GENERAL black men and women seem to have a smoother sounding vocals when they sing compared to white people or Asians or Arabic. I don't like it when people cant take generalizations, because they are everywhere in everyday life why try and avoid them, deal with them always knowing there are EXCEPTIONS!