Marketing is all about identity and visibility. Both of these things demand a well-designed campaign. There is no other way to go about it, unfortunately. This is because your brand or product identity will almost always be tied to the specific aesthetic elements you use to market yourself with.
Needless to say, business owners and designers alike will need to give this some thought. Whatever you do, keep in mind that your design should always highlight the message you are trying to convey. It should not serve as a distraction.
Design Central is a blog dedicated to helping readers understand the importance of their design choices.