One good word beats a babble of bad ones

Adam and I in the food court. Up ahead, a seasonal salesman hawking a remote control car. Only this one is racing along the wall, like a spider. Never seen that before. I ask how the car sticks to the wall. The salesman turns to me, as a seven-year-old prospective customer, only a couple of minutes ahead of us on this learning curve, talks his way into a turn at the controls. 

The salesman says, "It's ... uh, air. See, air. There's these holes, and uh, air ... well it's just air..." The seven-year-old, hands on the wheel and eyes on the wall, leans back toward me and speaks with cool authority:

 "Suction." 

The salesman nods. I nod. Nothing more to be said.