Transformed Monsters: Justification or Truth?

Many, many people have written stories from The Monster's perspective, whether the Monster is Grendel or a serial killer. In truth, these stories aren't the product of modern psychology. The tradition goes back to Shelley's Frankenstein and even farther. 

The desire to creep into the "other's" mind and understand it is very old. The Epic of Gilgamesh presents a point where Humbaba, the giant or ogre that Enkidu and Gilgamesh have come to kill, presents his "side" and pleads for his life. Arguably, he is lying to waste time (Enkidu and Gilgamesh kill him anyway). But he gets a surprising amount of dialog. 

My favorite example of a justifying Monster is The Dracula Tape by Fred Saberhagen. Using Bram Stoker's own text, Dracula argues that he has been massively misunderstood. His "truth-telling" is  fun because he isn't entirely trustworthy. Ambiguous. Sarcastic. He doesn't present a Dracula transformed into a decent, virtuous, sacrificing hero. Rather, his "truth-telling" transforms him into...a guy who isn't quite as bad as people say.  

Monsters who turn out to be UTTERLY unlike their original characters are a little too much, like stories which turn out to dreams. Far better to have a Smaug who speaks half-truths than a Smaug who uses Bilbo as his personal therapist. 

Monsters should never be entirely stripped of their monster-selves, even when transformed.