That is because they write scared. They are so afraid to have their good characters do anything evil to the point of them doing the dumbest things. Then the villains are serial killers who murder their own family members. It is like they have no idea to make a flawed character without them feeling irredeemable and they have no idea how to make a heroic character without making them forgiving to a fault and foolish. It is like there is no middle ground.