Look at the assumptions you baked into your original plan. Did the city follow through on opening that new park across from your location? Were insurance rates what you expected? How many hours of accounting or web design help did you really need? Are your online inquiries out_stripping your face_to_face sales? Or vice versa? Sometimes no matter how much you research, plan, or test, things don't go as expected in a business. This isn't necessarily a herald of failure or a sign that you're not cut out for entrepreneurship. Life and the marketplace are both unpredictable, and plans need to be fluid and responsive. The "One Pressing Issue Plan" is simply a reflection of a normal evaluation process.
The main thing to remember in this section is not to provide new data, but to explain in detail data that has already been provided and to provide the support for that data. When you sit down to compile all of the elements of your business plan, make sure you have each section able to stand on its own merits. This means you should not reference other sections sending the reader (your potential investor) back and forth between sections.