Why do Sotapannas need faith?

I have read that the Stream Enterer needs to develop all the 5 faculties order to become enlightened. One of these facilities is faith. It is also said that they are beyond skeptical doubt of the Buddha's teachings and know for themselves the way out of suffering as they have the right view. Since they have seen the Buddhas teaching for themselves then, why do they need to develop faith in it? You only would need to trust someones word if you cannot verify their claims for oneself. I understand then why a Putthujana would need faith. So I am wondering maybe a) I am wrong in my understanding of what Saddha means... if so what is it and how why do I need to cultivate it or b) I am wrong in my understanding of what a sotapanna is and he is still needing to verify certain things. Can some one affirm which of these two are right? Linked Discourses 48.56 6. The Boar’s Cave Grounded >“Mendicants, when a mendicant is grounded in one thing the five faculties become developed, well developed. What one thing? Diligence. And what is diligence? It’s when a mendicant looks after their mind when it comes to defilements and things that stimulate defilements. As they do so the faculties of faith, energy, mindfulness, immersion, and wisdom are fully developed. That’s how when a mendicant is grounded in one thing the five faculties become developed, well developed.” Thanks