In her book Discoverability, Kristine Kathryn Rusch cites the acronym penned by Scott William Carter: WIBBOW, which stands for Would I be better off writing? It's the same concept as the economists' one of opportunity cost, but applied to writing. In a nutshell, while you're busy updating your Facebook status, or trying to create a good cover design, would you not be better off doing what you're really good at and which, ultimately, is going to earn the money, ie writing?