Courage...

...is required to harvest the value of dumb questions.

Grant McCracken: 

Ethnography begins with an act of humility and the declaration of igorance.

But the news improves.

The respondent will mock you at first and then something remarkable happens.  When they see that you are not going to cut and run, that you are so sincere about finding out about what they know, you are prepared to endure a massive loss of face to do so, they will take you in, sit you down, and tell you all about it.

So what do you want to know? And whom are you willing to ask, under what conditions?