As we move toward the end of the book, we begin to get a number of different perspectives on the story that we are being told. We see a naval newspaper that portrays Billy as a mutinous man with murderous intent, and then we see a sailor's poem that turns him into a corny mythical seaman. At first glance, both seem ridiculous because we know the real story. Or do we?
Looking back on what we have read, we realize that we never learn anything about our narrator or how he got his information about the incidents aboard the Bellipotent. For all we know, his story is just one more misinterpretation of what happened to Billy Budd. Maybe all along he has been portraying Billy as being handsomer than he really was, simpler and stronger, braver. What happens as we approach the end of the book is that we begin to re-evaluate everything that we have already read, to see it in a different light. If we're literary dorks, which we are here at Shmoop, then we might even start over and try reading it all again.
Of course, if we question everything in the book, then the entire story seems to slip away from us. We're left to wonder: What's the point of telling this in the first place if you're going to get it all wrong anyway?
The point is that the narrator is making an effort to get it right, striving for an objective view of things even if he knows that he can never actually capture it. If Billy's story is completely forgotten, then there's nothing to learn from it and it will be just like it never happened. In a way, the ending is another bit of honesty. It makes transparent the process by which events are distorted as they are re-told, the ways in which our memories and miscommunications convert real world happenings into stories and fictions.
In a way it's a bit like the curtain falling on a play that you didn't realize was a play. The curtain signals the ending, but it also signals the fact: This is a play. It may be a re-creation of real events, but it isn't real.
The take-away point: the ending (like all good endings) sends you back to the beginning, and forces you to question what you thought you already knew.