in (one's) (infinite) wisdom
Used ironically when describing one's action or decision that the speaker thinks was particularly stupid or ill advised. The management, in their infinite wisdom, decided to cut employees' benefits while demanding that they work even longer hours.
in someone's wisdom
used ironically to suggest that an action is not well judged. 1992 Rugby World & Post In their wisdom Ciaran Fitzgerald and his selectors decided to dispense with the incumbent, Rob Saunders , and bring Aherne back for his thirteenth Irish cap.