Stories are about people. When you get to the heart of what makes a compelling narrative, the only thing that ever really makes a story resonate is fascinating characters. Watership Down? Rabbits that are people. Temeraire? A dragon that’s really a person. Basin and Range? Rocks that are… well, people. A novel with complex and believable characters and a wooden plot is a great book. A plot heavy book with wooden characters isn’t worth your time. We’re pack animals. This is why reality TV is so incredibly popular, because the noisome wretches on Jersey Shore or Duck Dynasty are PEOPLE, and we want to know what becomes of them, for good or ill.
And here’s the thing about people: they aren’t perfect. People make mistakes, frequent and horrendous mistakes. We screw up early and often and horribly. The best protagonists in all genres, fantasy included, are equally flawed, not so horribly that we want to see them burn, but enough so that we see our own errors reflected in theirs. Because if our favorite fantasy characters can fall so far and find redemption, then maybe we can too.