The voice? The odd tan? The sincere squinty eye look? The overly large boobs for that tiny body? Did I mention the voice (the many reasons to not like her). Then there is the character and the plots they keep giving her.
OK here is my take on the whole rehabilitation thing. Carly always had that something to her character that made her likeable even in spite of all the bad things she was doing at first. You could feel that she was acting out because she was damaged somehow on the inside and its the same thing with Rick. Yes, hes horrible and has a tiny heart BUT..... the actor is so dang good that he is able to play this character in a way that I can't help but feel compassion for him because I know its coming from a place of deep hurt and I keep hoping that someday he will find happiness and forgiveness.
I don't feel any of that for Sam. I don't think Kelly M is a good enough actress to pull it off. To play a bad guy with that deep inner core of hurt... think about Todd on OLTL. He's the master at that sort of thing.
Anyways.. thats my take on it. I think with a better actress that maybe Sam could be played in a way that you can't help but feel compass and hope that she is redeemed.