The marketing planning (concretized in the marketing plan) is an essential organizational activity, considering the hostile and complex competitive business environment. Our ability and skills to perform profitable sales are affected by hundreds of internal and external factors that interact in a difficult way to evaluate. A marketing manager must understand and build an image upon these variables and their interactions, and must take rational decisions.
Risk _ in our marketing plan we shouldn't only concern about making money or positive points, we also should address the risk we are taking. for example it is common for a marketing plan to capture things like, "require additional staff to handle sales call", "additional investment from the management budget will increase chances of increasing 10% sales target" and many more. Imagine if you can factor your risk earlier and think through it, wouldn't it be better for you?