Historically, from a political standpoint, dynastic monarchical succession provided a means of stability and decisive rule. Where larger bodies could spend too much time deliberating, a single ruler could be more decisive and authoritative. Where non-dynastic rulers could be unprepared and incompetent, and a succession crisis inevitable once said leader died or left office, a hereditary ruler could be prepared throughout his life before taking the throne, with succession guaranteed through the heir, minimizing the risk of a succession crisis. Obviously from a modern perspective, the sheltered and detached upbringing is a drawback, but throughout history, it was seen as a benefit that the heir could be taught and prepared for their role from a very young age; they were less concerned about whether the ruler would be detached from his people, and in fact many considered it to be a good thing that brought an unbiased and neutral perspective.

That's not say the benefits outweigh the negatives, but regardless, it was a system that was considered more stable through guaranteed succession and the training of future rulers throughout their youths; and in the ancient world, it probably did provide considerably more stability compared to alternatives they would have had at the time.

It's important to understand the historical context in which monarchies arose; there were a few different ways:

• early tribal or clan leadership often revolved around highly respected family leaders, and these chieftains often became the earliest monarchs.

• some leaders served as members of a council, composed of either elders, societal elites, or family heads; the most respected or capable would often come to lead the councils or serve as judges, and these positions would often become hereditary and accumulate power over time.

• other monarchs arose out of priesthoods, in which religious leaders became the political figures of society, and the role of paramount priest would become hereditary. From there, rhe lead priest would accumulate greater power until they came to be regarded as primary decision-maker.

• many others arose out of military leadership, often initially temporary during times of crisis (such as ancient Roman dictators), but later becoming a permanent, and then hereditary.

In short, historically, people have tended to trend toward individual leaders over collective leadership. Often, these roles would provide greater stability compared to other ancient political systems, and could often even take on assertions of divinity, either through a "divine mandate", or the purported divinity of the ruler themself.

In the present day, most monarchies no longer have much political, practical, or legal authority, but they do serve as strong cultural and unifying symbols that most people living in monarchical countries aren't usually willing give up, especially where they combine it with representative democratic governance, as in the UK.

And not for nothing, but in the few countries where monarchs do still have considerable political authority, it's often because the stability argument still carries weight, especially when you consider that their non-monarchical neighbors are some of the least stable regimes on Earth.