In March 2011, maverick, who had been an AH.com moderator for some time before that, had abused his moderator powers by hard-deleting several threads he had no right to, in an effort to, in his own words, “improve the board”. Such moderator behaviour was unprecedented and resulted in the permanent loss of several threads. In the end, he was hoist by his own petard, as most of the deleted threads were his own works (still a pity, as he is a talented writer).
By that point, maverick was apparently getting increasingly frustrated with the board and so wished to wipe all record of his time on AH.com off the servers. This led to him deleting many of his own threads, breaking one of the main rules Ian had laid out to his moderators. He was banned shortly after this was discovered. See the banning post for more information.
Some of maverick's permanently lost timelines and other writings have since been partially recovered, but only in the form of mirrors of the threads' starting pages. Not in the form of the threads in their entirety, unfortunately.
One of the more important threads that fell casualty to maverick's ill-advised behaviour was the original Hall of Infamy IV thread. It was lost during its infancy, though, so it was easy to replace with a new, identical thread.