An ordinary exchange can teach somebody whether asking again will feel safe.

Small interactions carry information about the future. Someone asks where the forms are, or repeats a question, or admits they did not follow, and how you answer becomes their estimate of what a second question will cost. Sighs, speed and a slightly flattened voice all register. Nobody announces that they have decided to stop asking you things, they simply stop.

Watch your first two seconds when someone asks you something basic. That is where the decision tends to get made, and slowing down there does more for a person than any general invitation to ask anytime.