Board Thread:Naruto Discussions/@comment-5054236-20150717003436/@comment-1512913-20150718151451

Black Zetsu at least suggested Hagoromo awakened the Rinnegan. Can you imagine a baby born with the Rinnegan? We were never shown that to be the case. If the Rinnegan really has to be awakened and is similar to Sharingan in this regard, then there has to be some trigger to activate it, just like mental trauma etc. are for Sharingan.