Inefficacy /(?)/

In·ef·fi·ca·cy

Inefficacy

n.
  1. Lack of power to produce the desired or proper effect; inefficiency; ineffectualness; futility; uselessness; fruitlessness; as, the inefficacy of medicines or means.
    The seeming inefficacy of censures.
    The inefficacy was soon proved, like that of many similar medicines.