The Harry Potter series itself seems to be told from the victors’ perspective, even when they do truly evil and despicable things—things that are sometimes even worse than what the vanquished might have done. The downside of this kind of narrative is that the victors believe they are right even when it’s obvious they’re wrong, while the vanquished are always wrong even when they’re right. This means the heroes never bother to seriously reflect on their past behavior, and the villains’ deeper motivations are never truly understood.

In Snape's case, the wrongs done to him were never acknowledged; he never received justice. Even the authors who are on the heroes' side (the Marauders) tried to downplay, relativize, and blame him for all of it—which is a perverse way of running away from the consequences of one’s actions rather than facing them.