One of the fundamental misunderstandings prevalent among intellectuals who deny the divine and spiritual basis of reality; is that they assume evil is ultimately a kind of selfishness. The assumption is that an evil person is one who pursues selfish goals without regard for others.
These secular materialists believe that, although selfishness may take different forms in different people, evil is ultimately self-gratification - aiming at what I want, and what gives me gratification; instead of taking into account what other people want.
This, in turn, leads to the idea that altruism - which entails self-sacrifice supposedly for the benefit of others - is the highest virtue.
The reason I italicized "supposedly" for the benefit of others; is that the benefit of other people is, in practice, conjectural - and often disputed.
What happens, in practice, is that everybody claims to be doing what they do for the benefit of others, and constructs rationalizations to 'prove' this - but there is no objective standpoint from which to evaluate these counter-claims.
Especially since comparing benefit involves trying to balance multiple and incommensurable factors - as when comparing the supposed psychological benefits of supposed-freedom or supposed-equality, with (for example) measurable material disadvantages such as increased death from violence, increased incidence of rape, increased disease and poverty.
(These examples are relevant because many secular-left political triumphs that have been justified by benefits of 'freedom' or 'equality'; are accompanied or followed by large material disbenefits such as those listed.)
Because large-scale or mass benefits cannot easily or uncontroversially be measured; it is common to try and discern evil from good on the basis of 'who benefits' from some course of action: in law, such a principle is termed cui bono?.
Thus, a great deal of debate concerns who benefits from policies in terms of money, or power - or, less often, some powerful gratification such as greed or sexual lust.
The idea behind this is that evil is self-gratifying; and the implicit assumption of such reasoning is that those who propose some course of action but do not benefit from it, but who instead lose-out from this course of action, are not motivated by evil...
The idea that those who lose-out must therefore be altruistic in motivation; and, as such, be good.
Yet this is not true; because evil is often self-destructive.
Indeed, evil is always self-destructive - in the end; because the nature of evil is to oppose Good (i.e. to oppose God and divine creation).
This means that, since all beings are created by God - and live inside God's created reality; all evil must, sooner or later, oppose its own well-being.
My point here is that we ought not to be blinded to the operations of evil by the fact that evil people (i.e. people who have affiliated to the side of evil in the spiritual war of this world) may advocate and work-for policies and actions that will harm themselves, and their own well-being.
Also, that self-destructive behaviour is not thereby altruistic. Just because a person or institution acts against their own gratification and best interests; does not mean they are acting for the well-being of others.
Often enough - the covert intent is to cause harm to all of divine creation, including themselves.
In other words; while evil may be selfish and self-gratifying at the expense of others; evil will eventually become merely spiteful, merely destructive, merely negative.
This is not self-sacrifice; but self-hatred.
Evil hates itself because its-self is a part of God's creation, hence ultimately Good by its nature.
Attempted self-annihilation, suicide, is therefore the inevitable and only end point for successful evil.