Every business has some form of marketing plan in place whether they know it or not. The plan is not always intentional or strategic, but if it is working, it is enough for some. I have worked with companies that proudly boast, "we have never done any marketing". Unknowingly these companies had some of the best word of mouth marketing plans in place. This article from MarketingProfs deals with the tendency to lean on one form of marketing over another. This is a great article. Read here.