Sometimes it looks as if evil often wins. We have only to look at all the atrocities and victims who cannot be brought back to life through the evil deeds of others. But there is one way in which evil does not win, even if seems to have achieved a trivial and superficial aim in terms of the infinite time of the universe. Evil-doers always damage themselves, maybe not in terms of perceived status or wealth but in terms of their own personality and standing as viewed by those who are genuine. Those who try to challenge the good natural law will be dashed down like Lucifer to burn in Hell as their works cannot influence the after life, whatever they do here. Lucifer,an angel who wanted more, is too big for his boots and wants to 'have it all' but 'good' or natural law is in his way and he fails. The link below will help you to see how this is laid out in the poem:
Philosophy presents itself in such a response. Be prepared to assess differing conceptions of answers here. I am not sure if good always triumphs over evil. The term "always" is probably where I feel there is the most amount of ambiguity. I would suggest that the personal set of beliefs an individual has might help them understand or conceive of an answer to such a question. Good, the concept of it, is pitted in many a situations against evil, and there is some battle between them. Depending on how one believes in the idea of spirituality, religion, the presence or absence of a divine power, is where the answer might be. For example, if one believes in a higher power, then there is the belief that evil might win at occasional moment, but it is part of a larger configuration where such instances are balanced out by a grander design. At the same time, if individuals do not believe in this higher power, evil might win, in general. This might be where an exercise in pure philosophy resides.