Muscle Memory. Just as your foot knows exactly where the brake pedal is in your car, or you hand knows where the snooze button is on your alarm clock, if you were to suddenly grow three inches, your body would have have difficulty finding these items, you would need to re-learn the distances but it would only take a brief period of time. Since our bones, muscles, ligaments and organs don't grow at the same rate, our brain is constantly compensating for these evolving differences and sometimes it takes time for instinct to find its way. I grew out of my temporary clumsy stage only for the unfortunate malady of another growth spurt to reassert itself several months later. D'oh!
A friend of mine had an eight year old son who stood at five foot ten. He was extremely tall for his age. This eight year old boy had a bed wetting problem and his parents punished and humiliated him severely for it. His problem (besides bad parents) was that he had an adult body with an eight year old child's kidneys. His bones and muscles grew fast but his kidneys and other organs hadn't caught up yet. He was constantly hungry and had a voracious appetite. His body was processing adult portions of food but his kidneys couldn't keep up. He couldn't make it through the night without the need to void three or four times. This unfortunate and uncontrollable process often happened while he was asleep.
My German Shepherd dog could be left locked up in the house all day and if I had to be away, she was able to "hold it" until I got home late in the evening. For many dogs, their mutual body and organs were designed for their size. That is the way God/Nature/Time had designed them through the process of natural selection.
Enter man who then begins to mess around with canine breeding and DNA. We're not as proficient at evolution as God/Nature/Time and have bred animals who no longer have sympathetic body parts designed for their breed, size, metabolism and body.
Sure, you can figure out a way to take the tires off of a Hummer and put them on a KIA but it will look really stupid and not be very functional. Likewise, you can probably figure out a way to take the KIA tires and put them on your Hummer. Again, it will look really stupid and will definitely not be very functional. Why do we do this to dogs?
So the next time you leave your dogs locked up for ten hours and you come home to find that they messed in the house, don't blame them. Blame your breeder. And the next time you come home after having left your dogs locked up for ten hours and there is no mess, praise both your dog and God/Nature/Time for their time tested and perfect creation.
There is one other thing; Why are you leaving your dog locked up for ten hours? What's wrong with you? At the very least, hire a dog walking service to come over and let them out one or two times each day.