I've had my dog since he was 8 weeks old and going through all the training phases and staying patient with him was hard....but I always think how many times he's patiently waiting for me for anything. He's like velco to me, if I go to the bathroom to shower, he naps on the bathmat. Even after a long day after work and I don't really feel like doing much, man, walking with him is the best thing.
When I used to live in Richmond near the airport, during the spring-summer months, I would take him to Mcdonald beach near YVR every morning. You want to see pure joy, the look on his face while he runs up and down the sand by the water...how can you not smile.
We just had a child not too long ago and the changes in him are so profound. He used to want to be the centre of attention all the time, but now, he understands that the baby needs taking care of. It's cool to see that when the baby starts to cry after waking up, he'll run over to his bassinet to see what's up. When we change the baby's diaper, he always stops what he's doing and runs to us to "help" out...even in the middle of the night.
Short version, dogs are awesome and give us their unconditional love. They deserve it in return.