Who talks and who is heard
Within five minutes you will know who narrates, who quietly solves and who waits to be asked. The interesting part is the gap between the two: the teams that escape are usually the ones where the quiet solver gets heard early.
How information moves
Almost every team that runs out of time had the answer somewhere in the room and never said it out loud. Watch how your team handles a find: do they announce it, or pocket it and carry on searching?
This is the single most transferable lesson. It is the same failure mode as a project where two people are solving the same problem in different tabs.
What happens when you are stuck
Some teams ask for a clue at four minutes. Some sit at a lock for fifteen rather than admit they are stuck. Neither is wrong, but it is worth noticing which one your team is, and whether that matches how they behave at work.
Running it as a proper exercise
If you want more than a nice afternoon, tell us in advance. We can put teams in matched rooms, record times and give you a results sheet. Then spend twenty minutes afterwards on one question: what did we know that we did not say?