Board Thread:Episode Discussions/@comment-1181222-20180913151539/@comment-31099706-20180915163119

I feel Yamato is more for guarding people that come from outside the cave, then the ones coming outside. Orochimaru has both dangerous enemies and allies that may not be as strong as him, but will come for him. Yamato is strong enough to survive against certain powerful people.

And I believe Yamato sends active info about the cave and Orochimaru's research to the leaf. So, if things don't come. The Leaf will start to suspect and check on it. Orochimaru is powerful, he is sneaky too, but he can't escape from someone like Naruto, who can sense emotions and chakra from far distances.

Why I believe Yamato is for guarding people from the outside is because the cave isn't exactly sealed. Karin, Suigetsu, Sarada and Boruto all came in and out of the cave with different passages. If The leaf actually wanted to keep the whole cave secured, they would go for barrier jutsu over the entrance. And someone like Orochimaru can simply re summon himself to the Ryuchi cave, like Sasuke did.

Orochimaru staying in the cave, as I would believe, is on his own interests. Freedom in experimenting, and people actually giving it important value, what more would a scientist as crazy as Oro ask for? He's also there to help his obsessed 'wind', as he mentioned to Naruto about the research on the dimensions, "I'm more than glad to help Sasuke kun" or something like that. So, Oro has turned into the good guy kind of guy, just not with talk no jutsu, but get killed and get revived by the same guy thing.