Maybe it's future-proofing? We're already sitting at level 4 Fire, Blizzard, and Ruin at level 70, and I don't know how many expansion we will have in the future. If we were to use those names, the last one is -ja at level 4 if I'm not mistaken. Then we would already have the strongest version of Fire, Blizzard, and Ruin the game could possibly have right now already.