Probably because they listen more than they talk... Your statement reminded me of a funny dog & car story. A friend of mine is a Model T guy & a dog guy. On most nights he takes the dog for a T ride. Its like clockwork, at around that time of the evening, the dog sits there & stares at him until he says, "Do you want to go for a Model T ride????", then she runs down to the garage. She used to get in first, until a few years ago... One evening he had the T in the driveway warming up, the dogs were in there, because they always had to get in first, & he left the car for a minute. When he came back, they were gone. He found them in the bushes across the road at the bottom of the driveway, the T still running & the dogs still sitting there - a little shocked, but no harm done. From then on, they won't get in until he is in there at the controls. Smart dogs!