When writing a business plan you sometimes end up locking yourself away. You might have unique ideas which lead you to seek some isolation and secrecy, or if you are going to be a sole trader you may only have one person to consult namely yourself. But it is fantastic to try and get broader input on your business plan _ whether from a professional, or simply from friends and family whom you trust. I say that because of course you need to be careful with commercially sensitive ideas, as you do not want to pass your plan on to someone in the pub who then starts your idea before you across the road.
Fundamentals, Cycles & Trends (FC & T's): Your plan, if done in advance and thoroughly, should provide and excellent foundation from which to work. Even the best plan still has to react to outside forces that will influence your best intentions. Identifying certain fundamentals, cycles and trends that may impact your company is a prudent way to being able to develop a contingency "plan B" in the event an outside force rears its head. A series of key FC & T's should be monitored throughout the year so that if required, your plan can react. Certain FC & T's may include wholesale pricing, weather, commodity markets or labor market impacts that are out of your control. In my opinion, developing contingency plans in advance for these outside forces at least gives you a fighting chance to react favorably.