Basically i was wondering if at any point there has been a monarch that actively prevented their own country's politics from working properly for any reason, by just not fulfilling their purpose of monarch
Sorry english isn't my first language i can try to reformulate any part, and thanks in advance for the response !
Henry VI of England (1421-1471) might be a good shout. He was generally ineffectual and uninterested in many aspects of Kingship. In 1453 he suffered a mental breakdown, and England was ruled by the Lord Protector: the Duke of York until December of 1454. I don't know if fulfils what you were looking for, but Lord Protectors existed in England for this purpose and did at least in this instance effectively rule for a year.