The other day one of our engineers called me over to show me a bug she'd found. I was going to thank them for alerting me and head back to my desk. But I recalled a similar instance from earlier that week when I was the one showing a bug to a coworker.
In just a few minutes debugging together at my machine I learned a ton about some of the darker corners of our backend, as well as some useful language for talking about this particular issue.
So instead of heading back to my desk I stayed there and we went through analyzing the root cause of the bug together. It took ten minutes of my time. We fixed a bug. And I think she learned a ton.