There's a whole world out there that they can see from your house but "aren't allowed" to go. The more independent of them take it upon themselves to "go anyway". My Hannah has gotten loose around 4 times. She was having a ball running around the neighbors backyards with my husband and I chasing and calling her. We'd get close and off she'd go in another direction. On the third time we discovered that if we didn't follow her she didn't go as far. So the last time, I didn't go one step off the property, but sat on my doorstep with a cookie and a leash in hand. After running around the house across the street for about 5 minutes, she came back home and walked right up to me.

I have practiced the "come" command every day since Hannah was a puppy, but she does a quick mental calculation in her mind, "Would I rather "come" and have a treat, or go exploring?" and "go exploring" will probably take top priority. I know what a disappointment this is when you have had other dogs that aren't inclined, but I would simply make up your mind that you will have to be very careful that she doesn't get the opportunity. She may be one of those dogs that will improve with age or with training. With Hannah, I don't know that I will ever find out because unless another accidental escape happens, I'm not going to experiment.