Ever notice that after a while, you get tired of the same things -- whether foods, TV shows, work responsibilities, or -- dare I say it -- people? Several people have asked me why this happens, so I thought it apropos to create a post that addresses this phenomenon. The more we're exposed to a given stimulus, the less satisfaction we derive from it over time. In psychology and economics, this is known as the law of diminishing marginal utility.  Here's the definition provided by BusinessDictionary.com: "The law of diminishing marginal utility is a psychological generalization that the perceived value of, or satisfaction gained from, a good to a consumer declines with each additional unit consumed or acquired." In other words, you can only eat so many Big Macs or watch the same movie so many times before you become completely sick -- which is termed disutility.  In advertising, wearout is defined as the declining effectiveness of a commercial or campaign ...