The title of expert should leave enough room for an ordinary question.

Expertise makes certain questions socially expensive. Once you are known for knowing, a basic query feels risky, so you nod, guess, and stay quietly wrong about something a single sentence would have fixed. The title starts protecting your standing instead of the work. Real command of a subject includes being able to say you have never understood this part.

Ask one basic question this week in front of people who assume you know. Notice how many of them turn out to have been wondering exactly the same thing.