It’s happened to me. I’m terrible at the whiteboard in these situations. I have a severe disdain for whiteboard sessions. I’m an experienced engineer, but I’m likely to fumble at the whiteboard.

When I’ve interviewed candidates I make it a point to talk about something they’ve worked on and drill down into it. If they need the whiteboard to convey something, that’s great. We’re having a conversation and I’m not giving them a test. I’ll ask about potential optimizations and/or improvements, but I try my best not to make things adversarial. This has worked out really well. The best conversations have resulted in great hires in my experience.