[Help] Trying to figure out my dog

I have a small terrier type dog of unknown parentage, about four years old now. Raised from being a very tiny puppy. Very affectionate and faithful companion, and strikes me as above average in intelligence. There are several things I don't understand about her, but one in particular mystifies me and I wonder if anyone might be able to provide any ideas about the psychology behind this behavior:She can bark, but does so rarely, usually in response to other dogs outside our gate. But here is what I don't understand. If I forget to let her out of our gazebo in the morning, or if she is in our garage area and the door is shut, she absolutely does not bark or whine to let us know. I don't have a problem with that, but here is my question: Why would she not want to alert us to the fact that she wants in or out? I have never seen another dog that patient. via /r/dogs http://ift.tt/2rQJ0CJ