Leonard has that cute factor about him and always has done so it was inevitable that he would end up getting Penny- along with several other women after they had broken up. Roy and Moss however- don't have that appeal in the slightest. Roy is an out and out slob and Moss is far too intelligent for his own good. They both make no effort with their appearance, with Roy wearing t-shirts emblazoned with nerdy slogans and having unkempt hair, to Moss with his huge, thick rimmed glasses, checkered shirts and giant Afro. A reflection of this is when we finally get to see inside Roy's apartment, which more often than not is a reflection of most computer nerds.