inefficacy

/ɪnˈɛfɪkəsi/
noun
  1. Lack of ability to produce the desired effect; ineffectiveness.
    • Many people complained about the inefficacy of the air purifier in removing smoke.
    • The inefficacy of the vaccine against the new variant was a major concern.
    • The inefficacy of the team's strategy became obvious after they lost three games in a row.
Antonyms
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