Board Thread:Theories and Speculation/@comment-31222592-20180411213057/@comment-734582-20180520094813

LoneNinja wrote: The reason they didn't have the sixth paths were because Obito couldn't grant them those abilities since maintaining control over multiple tailed beasts with Jinchuriki's were already hard to begin with. It was never explained whether he couldn't or didn't. Kakashi speculates that he either couldn't (due to biju control) or didn't (because each path was already countered before).