I don't know if it's true or not but I've read that it is because small dogs have a faster metabolism (that is true) than big dogs. Fast metabolism, small bladder, more frequent urination.
While your yorkie might be able to do better than two hours, you can't compare day to night bladder control. At night everything slows down and the brain releases a hormone that makes the kidneys produce less urine. Same reasons why we make it through the night without going. |