Chris Brown has a theory on why the woman claiming he punched her in the eye is making her allegation -- he says it's because she's just too ugly.
Chris posted this video and then deleted it ... putting Liziane Gutierrez in his crosshairs. As we reported, she claims he brutalized her in a Vegas club ... something he denies. And, as we reported, she's gone after other celebs like Jason Derulo when she gets pissed off.
Chris also posted this threatening message, "I'm going to be hella rich after all the lawsuits I file from these crazy individuals who keep lying on my name. Happy NEW YEAR! Time for some of us to grow the f*** up.