Inefficiencies rhymes with:
deficiencies, efficiencies, deficiencies, efficiencies, deficiencies, efficiencies, deficiencies, efficiencies, agencies, agencies', agency's, conservancy's, constituencies, contingencies, counterinsurgencies, currencies, currency's, deficiencies, delinquencies, dependencies, discrepancies, efficiencies, emergencies, exigencies, expectancies, frequencies, insolvencies, insurgencies, malignancies, pregnancies, presidencies, presidency's, redundancies, regency's, tendencies, transparencies, vacancies
Inefficiencies sounds like:
impeaching, imposing, impugning, impugns, inefficiency, infusing, infusions, invasions, invoicing, invoking