I feel bad for so many villains, and I don't blame them. I feel bad for Tigerstar, Brokenstar, and Hawkfrost. With Tigerstar. He got a bad mentor, and his father left him when he was only a kit. He had no father growing up, and he had a mentor that pushed him constantly. I think if his father had been better, and stayed, Tigerstar would have been a noble leader to remember. With Brokenstar. We had no mother, and was abused. Lizard what's her face never cared. She didn't even care about her kits. Then he was bullied by his den mates when he was a kit. He tried to help Yellowfang once, then was bullied. He grew up around lies, and hatred. He was just upset. He never got the love he deserved. With Hawkfrost, there's not much to say. He lost his only brother when he was a kit, his father was evil, and his mother left them. He was all alone, with a few cats he knew, and the rest he didn't. He was probably scared, and wanted his mother back many times.
Tigerkit being judged by Goosefeather
Brokenkit trying to have fun with his mother before getting bullied
Hawk playing with Tadpole
Tadpole's death drove Hawk to the cat he was