As one goal is about to be reached, a new, more difficult goal replaces it. The real problem, however, is that they never believe they are worthwhile just as they are. If your work is your play and also your personal expression of life, then spending long hours at it is fine. So many people, however, hide from themselves in work that the term workaholic isnow part of the language. Chronic inaction in areas you know need attention can be an addiction.
Some people become habitually lethargic.
Not taking an action becomes an automatic response. That's the habit. You're stronger than it is. Set yourself a reasonable task and complete it. Show yourself you can do it, because you can.