When it's just a fancy name for a bit of terminology, that's what. Somehow, especially in game design rather than game programming, people have seized upon the idea of design patterns and decided that a design pattern is a formalised name for a concept we see often. So we get articles like this one over at Gamasutra which just treats game design patterns as glorified ways to talk about vague elements of gameplay.

Design patterns are not just formalised names. We already have terms for that: jargon, or more charitably, terminology. Standardised terminology is a good thing but we can do better than that. From fields of psychology, statistics, mathematics, drama, and literature, we can come up with theories of gameplay that not only describe a concept but explain how to model it, what it achieves, what the downsides are, and give abstract implementation hints. Let's not fool ourselves into thinking that game design is some mystical and indescribable quantity. Any other artist knows that there is some method behind the madness, so why don't we?