Every video game has an ending. Most have wonderful, memorable conclusions. When the game finally ends, you expect there to be some closure. You hope to see the heroes succeed. You want to learn where they end up, how the world has changed, and what your efforts have done to shape the course of history. If the ending has done its job right, there's an emptiness left in your heart. A void. You might even shed a tear or two. It's over, and you're left to ponder what happens next.
Sadly, some games don't end so well. They leave questions unanswered. Worse still, they have abrupt conclusions that don't shed any light on the events you've grown to care about. That is, if you cared about them at all. They gloss over character arcs, forget key moments, and simply do not care about whether the ending even makes sense, let alone tying up loose ends. Some, like Star Wars: Knights of the Old Republic II- The Sith Lords, simply ran out of time. Others, like Borderlands, left out major plot elements, and left many unanswered questions lingering.