Mechanical metamaterials allow for elaborate physical properties to be encoded into the very geometry of a structure, allowing a dramatic reduction in complexity compared to a conventional machine with similar functionality. It is notable that many features within mechanical metamaterials are inspired by previously existing biological materials, but while biological systems are self-assembled and disordered, metamaterials are typically designed with ordered or periodic structures which are optimized but could malfunction in the presence of random defects.Here we discuss the role of disorder in mechanical metamaterials consideringthe examples of auxetic materials and random beam networks. Finally, we discuss an example of a simple mechanical metamaterial inspired by the mechanics of a carnivorous plant.