The expert should explain which details matter before presenting all of them.

Expertise includes knowing what can be safely ignored. When a specialist opens with everything they know, the listener has to do the sorting, and the listener is exactly the person least equipped to do it. Completeness feels like honesty from the inside, but from the outside it often reads as evasion, or simply as noise.

Whenever you know more than the person you are talking to, lead with the two or three things that will change what they do. Say plainly which parts are background. Offer the rest as available rather than delivered. You will be trusted more, not less, for having narrowed it down.