The waiting room is where you find out if you brought anything to think about.

Forced empty time shows you what you actually brought with you. No signal, an old magazine, and a name being called every few minutes is a fairly honest test of whether there is anything running in your head that does not need a charger. Most people discover they have outsourced the whole department.

Carry something in with you on purpose. A question you have not solved, a book, a letter you owe someone. Then the twenty minutes turns from a hole in the day into the only part of it nobody can interrupt.