I am bad at faces

I was standing next to someone pretty darned famous this morning in an elevator, and literally had no idea, except that I noticed their face was exceptionally symmetrical. It's not that I hadn't heard of the person, or had never seen them on TV, or didn't roughly know what they looked like. My brain just has a terrible time comparing the particular face I'm presented with against its stores of names, and nothing clicked until the frantic chattering when he/she left the elevator.