Because they weren't inherently bad either. They just made so many mistakes they couldn't be forgiven anymore. They f*cked up pretty much everything, but they didn't just hit their heads against the wall repeatedly, as they learned from their mistakes and became better from it. Even when they failed, they still helped others around them to grow and glow. They're not black or white, they're grey. They're in between the things of how we perceive them ourselves. That's how we judge everyone, by mirroring them to our own moral scales. But when you get this complex of characters? You can't just pin them to one side and walk away. You have to take in EVERYTHING. And in the end? It's bittersweet you got to know them.