why you have to be rude?

being rude is a very bad thing .... every time that someone does something stupid or when someone dies all of their teamattes call him a noob .. what makes me very angry is that the guy who died knows that he made a mistake but his teamattes kepp calling him noob and when he says to them to shut up they all cry like a ;little baby and they say i will report you noob .. you have 4 reports noob.. I really do not know the reason to call someone a noob cause 1 time he did something wrong