Both of my dogs are of the shy type but Max (Black/White - Male) is more outgoing than Pookie(Brown/White - Female) and I've learned a lot by observing them.
When Pookie was young she would pee at the mere sight of a new face. While she's outgrown this, she's still the shy girl and misses out much of the joys of being a dog as a result of it. You'll rarely find her in the main areas of the house as she prefer the peace and quiet of her hideouts - only coming out when she wants attention, food, or to go outside.
Max, while shy, acts more like a normal dog than Pookie does. He always wants to be where the action is at and I would argue that his experience, as a dog, is more enjoyable.
It's not difficult to see the relationship between these two dogs and humans. There are people that tend to prefer solitudes, either because they truly enjoy it or because of shyness, and others that enjoy being where the action is at. Both are going through the same experience of being human but one may be living it a bit more fully than the other.
Regardless of the type of life that you decide to live it's important to note that life is, painfully, short and will end the same way whether it be in the comfort of your house or on an adventure and, as far as we know, we only get to be human once... make the most of it.
As far as Max & Pookie goes, they're the best dogs in the world and are currently living their elder years. The thought of loosing them is painful to me but also a reminder to make the most out of the time we have left together.