The "One Pressing Issue" Plan: Business planning does not stop the day you open for business. Under the best of circumstances you should be revisiting your plan once or twice a year to see how things are going, and where perhaps you've veered away from your original goals. Remember, changing the direction of a business isn't always bad, but it should be intentional.
Now as I said, there are many other reasons too. After graduating from college, I started out in manufacturing as an engineer in a pretty large company and now, 45 years later, retiring as a of Director of Manufacturing, I have discovered an awful lot about business. Not only did I learn and teach a lot about business, I worked with small business owners as well. I've learned that it comes down to this. Too many owners work hard in their business but less on their business.