Naturally, having developed these conflicting interpretations of 'Good', I can't leave them alone. I am compelled to confuse things by mushing them together to form some useful whole. The instincts evolved. They are still evolving, though very slowly. Gene pools cannot adopt anywhere near as fast as cultures.
Cultures evolve too.
What works for one people, at one place, at one time, might easily fall apart a generation or two down the road. From within a culture, especially for the old, any force for change might be easily mistaken for Evil. That's just wrong. In these times, with technology inducing rapid changes, flexibility has got to be a virtue, and rigidity a high risk low probability of reward proposition. There was another element I mentioned briefly, then discarded.