Many people create a business plan when they are first starting their business. As their business continues most will change in some way (new competitors, new opportunities etc). If that is the case, shouldn’t you be redoing your business plan on a regular basis?
Imagine trying to follow a road map when the road system has changed, isn’t that the same as trying to follow a business plan when the industry keeps changing?
Keep your plans up to date, it will make your life much easier.
Have a great day!