It's not a secret that repeating an action makes it a habit. The same applies to marketing, as my boss (the wonderful Deb Cochran) always says, "do it once, use it seven times."
Television and print advertising are the most notable, of course. How many times do you see the same commercial during an hour-long program? In order to get the brand's message across, the message needs to be repeated to the consumer so that the consumer can retain that message. The condition, of course, is that it (a) needs to be a "good" message and (b) a well-thought out one (in other words, you've got to think about every detail and make sure the sum equals your intended message).
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