Origin didn't follow the pattern, because they were always tempted to put in names that had to do with them, eg. TCS Austin, and the TCS Winterrowd. As for the other ships, each class seemed to have it's own system. The Bengal class, for example, had names to do with Bengal. They had the Tiger's Claw, the Kipling... The Waterloo class had great battles - TCS Agincourt, TCS Gettysburg. The TCS Centurion didn't quite fit in though.