Love this topic.
Brian Tracy is really good. Some other great Autohors/Experts on goal setting agree that "Thinking from the End" is the best way to achieve all the things that you want.
Bill has a good point. Goals need to be realistic, but also should be made to stretch you or take you out of your comfort zone.
There seems to be two thoughts on goal setting that Bill touches on.
1. Set them High - "Aim for the stars cause even if you miss you'll still hit the Moon" -which is good if you are super driven. This method can burn you out and be a little demoralizing if you can't bear not meeting your goals. If you can step back and still be proud of what you have accomplished then this method may be good for you.
2. Being Realistic with your goals, which bill covered well in his post.
Another thing I do is try and make myself uncomfortable everyday. I look for ways to stretch my comfort zone as much as possible. Speaking to new people, making 20 extra calls. Door Knocking. Whatever it is - if you are always going a little further than your comfort zone then you are growing and in turn getting closer and closer to your goals.