There are many rumors about the famous Winchester brothers. Some of them are true, and some of them are not. Some say they are vengeful gods and some just say they are simply humans who have gone through too much. Who can say the truth? It has been said that the Winchesters were always like this, angry, brutal, violent, damaged beyond repair. But if one were to sit down and really research. If one were to look back to when their stories first started, it would become clear that they didn't start like this. They weren't always battle worn soldiers. They started off as most others did, as children.
Higher powers will occasionally look back on the Winchesters past and question how they had changed so much. Angels have done this. Even the king of hell will sometimes sit and muse over how much the Winchesters have changed. He would most likely lounge at a large polished wooden table, pouring over pages and pages of information. And he would coo at Sam's baby pictures and chuckle at Dean's first few homework assignments. And although it was unfitting as a king of hell to feel this way, perhaps he even felt a certain sense of loss over the Winchester's loss of innocence. They never really did get the chance to be children.
And so there is no doubt. So much has changed.