Aziz is funny. Always? No. But deserving of the label 'can feasibly generate actual laughs.'
Amy Schumer can, too. In fact, probably only like 50% of her act is vaginal slut humor, which is remarkably low for a female comic.
The fat Mexican guy definitely deserves a label of 'completely not funny and should die,' though. He's as bad as Carlos Mencia. Kevin Hart is also fucking terrible. Throw in Kat Williams, too.
And can't forget the classics, like Dane Cook and Jeff Foxworthy (and those other Jeff Foxworthy types who aren't even worth looking their names up).
So what do most shit comics have in common? They do the racial stereotype bullshit, be it redneck, Mexican, or black.