The Upgrade Disks were never planned to be actually made. After Yeq's accident he was desperate to invent technonolgy to fix his vision. In the process he created the Sensoral System and the Upgrade Disks. KMES found these very useful and often used them on missions. It has also been noted that Toa Ganon, during his influence by Akatax, has shown an interest in obtaining some. After Axolra Nui landed on Jadax Magna, the members of Kopak's expedition, along with their now ally Zoruxx, used the upgrade disks to prepare for the harsh conditions of the Jadax Magna desert.