Board Thread:Naruto Discussions/@comment-27296281-20170721061114/@comment-1512913-20170722041510

It's simple. If they could be generated, it would defeat the entire point of starting with a set amount of them. Furthermore, Kaguya is the only one shown creating one of nowhere and the only one who didn't start with a set amount, reinforcing the theme of her being the superior one as the progenitor of all chakra on Earth, with her powers being limitless.