I think she overthinks so much about giving the best advice that the advice ends up making no sense?
She's not great words, she's more a woman of action and expresses her thoughts and feelings by acting. All the feeling management of an esper, she manages them and expresses them through her powers and moves.
When she speaks, it feels like she's rolling a dice: it's either life changing words or things that don't make much sense to others.

With time, Reigen teaches her to express what she feels with words tho and she is good at carefully picking the ones even tho she often leaves them open to anyone's interpretation