I have often made the comparison of someone being plopped into a family in a foreign country to an animal being brought home to live with us. With so many similarities, there is one advantage the first scenario has- everyone is of the same species. Allow me to explain.
If you were suddenly taken and transported to a foreign country to live with a kind and caring family, there would be many obstacles you would need to overcome. The obvious and most important is the language. They don't understand you and you don't understand them. It would take a while to pick up some cues and words, hopefully enough to start understanding who these people were and what behavior was acceptable. Then there is the subject of habits and customs. This new family may live in the mountains while you were used to living on a beach. The food is different. The smells are different. The weather and temperature are different. It would take time to adjust to all these things, an adjustment made more difficult due to the language barrier. Add to all of this the memories you retain from your past. You had a family with siblings, or perhaps you were homeless but you knew where things were and who you could talk to, or maybe you were a lone child with caring parents. Whatever your memories, you have them. You had a life before this new family.
At least in that scenario, the new family is human, like you. You understand humans (for the most part, humans are very complicated beings), you can think like them, can move around like them. You know what plates, bowls, doors, cars, fireworks, and trucks are and that is a solid starting point. You can focus on learning the customs and the language.
Imagine now, that you were a dog or a cat or another animal. Everything is new, unnatural, strange, and without a common language, learning is more difficult.
While I have always known and believed these difficulties exists this point was driven home again by a beautiful long-haired German Sheppard named Krewe.
During our communication, Krewe made it very clear that he understood a lot of things and was particularly good at picking up emotional vibrations from his humans. Krewe was happy and felt love from his humans. He loved them back just as passionately. He did have some things that he just couldn't comprehend. The first question he asked me, and most important to him, was why was he separated from his family. He was not allowed in the Living Room because of his hair, but Krewe could not decipher the "why" he was kept apart. He could only understand that he was kept apart. When his human explained that it was only because of his hair getting everywhere and I repeated how much love there was for him, (also important to mention that the separation is not often at all. The family is very loving and engaged with Krewe), Krewe seemed to relax. He now had a logical reason, understood it, and was able to let it go.
One of the other important messages or exchanges we had with Krewe was regarding his behavior on the leash, especially regarding trucks and loud vehicles. Once we were able to understand why Krewe behaves as he does, we were able to come up with a plan and explain to him what was expected of him. It wasn't just about expected behavior, though; it was allowing him to understand that not everything is a threat making him spring to action. It was this understanding, from both humans and dog, that will make all the difference in the behavior.
As I've become accustomed after so many animal communication sessions, Krewe did have a few requests that seemed very reasonable. His humans also had a few requests that Krewe promised to work on. So you see? Communication is so important for healthy relationships, including communication between species.