seek help about back-up save

I just heard about how to transfer data fromonehlder to another but here's a parctical problem before me. If acording to said that the maximum amount of games is 30, how about after 30?Does it mean the nintendo system control the number of game on its controler by limit the back up game number? Does anyone has any idea on it? i just got 3ds this black friday, i'm not sure if i am right so thx in advance!