Design should not be given all the credit for why the Parthian bow was so effective.

An appreciation of the role design played in the construction of the Parthian bow only makes sense when the underlying reason for the bow's existence is brought to light. It is unlikely that the bow was designed to fend off the military forces of the Roman Empire, or that the Parthians had any other conquerors of similar might in mind. The Parthians were fortunate that their context and cultural imperatives conspired to give them the upper hand.

Context and cultural imperatives are key to understanding why the bow is shaped and constructed so effectively. Chances are a particular material or cultural orientation determined the path taken in the construction of the bow. Evolutionary processes to improve the bow would have ensured each new model was more effective. Each warrior craftsman would have added insights gained from battle or from whatever other killing or ceremonial act the bow was used for to inform the construction of the next version.

Design is an oversimplification and distinctly modern romanticisation of an aspect of the industrial creative process. Because designers 'design' things does not mean that because an object was created that it had a designer or designers and was therefore 'designed'.

A creative act does not require design, design only assists in shaping and giving form to an imperative.