So, you think all men (people) are basically immoral and it's a day-to-day, hr-to-hr struggle to fight the temptations and live moral lives?
Some men, on the other hand, never decide that they are against moral evil and do whatever looks good to them. Or convince themselves they decide what shall be moral or immoral and proceed to do whatever looks good to them. Such men only behave themselves when they see clear and present dangers in failing to do so, and are not uncommon.
And some men don't pay much attention to those dangers, which are ephemeral enough, and not the real reason to avoid immoral conduct. They think themselves superior because they see the shallowness of conventional restraints, and experience their freedom to choose evil as liberating. Occasionally this is a phase in wild young men feeling their oats and it issues in precious little, and maturity or worldly responsibilities cure it. But it can go as far as they let it, all the way to self righteous service to morally evil courses of action, "idealistically".
This is less common than either of the previous, but happens often enough to fill all of recorded history with endless crime. Evil is always with us because men are always free to chose it, and some men do. The rest of us then have to deal with them, by force.