All food products go off after it is cooked and coffee is no different. It goes stale just 14-days after roasting - It does not go stale on day 14 like Cinderella's coach but you can taste the difference.
What this means is that all coffee that you buy at the store is already past the magic 14-days so it has an unmistakable bitter taste that is best covered up with sugar and cream or other flavorings. When your coffee is fresh these things are not necessary. (Read my post about keeping your coffee fresh)
Like the Prince's Ball, coffee is a great experience before 14-Days but after that it loses a little of the magic.