Chara is the truth. Chara is the player who does the genocide run "because I want to see what happens". Chara is beyond morality, beyond petty things like good or evil. Chara simply is. And if at any point, Chara awakens in your game, then it is entirely your fault. Chara never lied, never spoke once until the very end of the game when you've already damned yourself. You call Chara worthless. Lying. Pathetic. But it took tremendous effort on you, the player, to awaken them. Hardly worthless.