Evil truimphs because good people are suffering from bad stomach. Period.
Having a bad stomach is not an amateurish enterprise but a human condition. Anybody can have a bad stomach. So why to blame the good people ?
Good people have had all the right aims to confront the evil. But aah! the pangs of pains, the unpredictable cycles of motion, and all that worries in the deep recesses of tummy restraint them to stand against the evil.