I think you have hit the nail on the head - the goals are endless to aim for and they are personal goals!  I started running 14 years ago to lose weight (which worked and has helped me maintain a healthy weight since then)  and then get hooked on the challenge of running and have had countless goals over the years.  There is always another challenge....

Have you recently started running?  Have you used the Good Run Guide 5K beginners training schedule?  Did this work for you?  Can you give any advice/encouragement for others who want to start or have just started?