IDW had done two different versions of the old Ninja Turtles comics. Big hardcover editions and new paperback ones. However, BOTH releases are missing issues and I don't get why. What is the point of releasing an incomplete collection? Like Volume 3 of the new versions includes issues 12,14, 15, 17, and then 19-21. What happened to 13, 16, and 18? That makes no sense to me.