Sometimes somebody is written in a story, then the author finds they are unnecessary and uninteresting. Too late; the chapter they arrived in is up! The greatest insult is to simply stop writing about them. They aren't given the dignity of a cool death scene that carves out the dead wood. They don't get Put on a Bus to go to college or get Killed Off for Real. They don't even get one last Hand Wave. They just very quietly aren't there, while the author weeps in shame behind closed doors and prays nobody else notices. This is the ultimate Chuck.
In Prison Island Break, numerous unnecessary but otherwise interesting characters have died rather awesomely. But the author regretted the presence of Nate Morgan so much that she didn't even give him a last-day-on-the-job scene. Anybody remember Nate Morgan? Of course not.