On more than one occassion in my career, I’ve developed a website for a business and the business has closed right before or after the site goes up. In each instance, it’s because the business owner has decided to go a different route — not for the site, but for the whole business. I once made a website for a wedding boutique and the owner later decided to go to nursing school.
Another such client was a general contractor in Brooklyn, New York. I was pretty pleased by the initial site mockup, and we even got most of it into HTML, but it was never published. I liked it because it was dark and I like dark colors with sharp contrast and straight edges. So, for posterity’s sake, here is a screenshot: