Unfortunately, this scenario can happen to a panel moderator: You ask a probing or challenging question to a panelist and .... they got nothin'. They stare at you like a deer in the headlights.
What do you do when a panelist cannot answer your question? Actually, you have several options.
The ideal duration of a panel discussion can vary depending on the goals for the event, the panel in particular, the number of panelists, and the audience's expectations. When deciding on the duration of your next panel discussion consider these factors.