monarchy: people get power because they happen to be born into it. they are presumably in power for a while and their descendents will inherit positions so they have at least 'some' motivation not to fuck everything up. on top of that most taxpayer money they receive goes back into the nation. democracy: people get power because they want it so much they are willing to do anything to get it. very short period in the position so they have a big incentive to push bad policies, enact changes that benefit their donors/handlers and renege on election promises. vast amounts of capital are drained into overseas coffers, moronic schemes or just vanish entirely.
United Kingdom