Michael Phillip On The Incentives of Monarchy

[T]hough subject to normal human failings, the long time horizons of monarchy is one of its distinct advantages. As economist Mancur Olson pointed out that, the longer the time horizon of the ruler, the more their interests tended to converge with those of their subjects. One tends to be somewhat more careful and accommodating the longer you and your children are going to be living with the consequences of your decisions. Of the three major Axis powers, the two monarchies (the Kingdom of Italy and the Empire of Japan) found it easier to exit from fighting precisely because they were monarchies; there was someone with sufficient authority to say enough. Nazi Germany had to wait until Hitler was dead (and assassination proved to be a less reliable alternative).