It is ridiculous to have a monarchy in the 21st Century. The hereditary principle is the worst way I can think of to come up with a new leader. Even if people had the challenge to come up with the worst way in the world to find a new head of state, this would probably beat it. Monarchs should be thrown away. We need to be able to elect a head of state. That is the way that a country should be run - by elections and people's choice, not just because someone happens to be born into a particular family.
I find it hard to believe, especially in western nations and democracies, that monarchies still exist at all. Sure, we've all heard that the monarch is simply a figure head, and that all good and well. But figure heads don't take your tax monies, have control over your military and decide whether a leader can be elected.
It's time for societies to grow up.
Monarchies are a throwback to a time of barbarism. In today's intellectual and educated world, country's are led by the people, in a democracy, with choice; it ensures that the voice of the people can be heard. In a monarchy, a single person is trusted to make decisions for all. With monarchy comes corruption, despotism, unfairness, greed, and a host of other historic problems, so yes, they are wrong.
In most modern societies a monarchy provides something Americanised democracies can't - a stable figurehead who isn't politically motivated. With very few remaining powers that are mostly ceremonial (Parliament can in fact legally remove the royal family were it in the public interest), the major argument of 'costng the taxpayer money' is dwarfed by the billions through direct and indirect income they provide. Aside from the obvious impact of tourism, in Britain's case the Queen as head of state of the Commonwealth provides a cultural link between many nations that would otherwise most likely share lingering animosity. Its often also a point of patriotism and pride - similar to how Americans take great pride in their flag and their anthem, we take pride in our monarch.
Of course, I'm a monarchist, and by no means represent a majority of popular opinion, but I hope I've highlighted how a royal family isn't simply an 'economic blight' on a country.
God Save the Queen!
I don't think it can be wrong if the people agree to being governed in that way. It seems to me that monarchs generally are figureheads that simply represent a long line of governance but actually have little to do with the running of the country. The English people seem to enjoy their royalty much as we enjoy movie stars.
Monarchies are not "wrong," but rather just irrelevant and outdated in terms of government. The British monarchy, really, is just for show. The members of parliament are the people running the British government, not the queen. Monarchies, I would argue, are not ideal forms of government, given that there are very few today and that the queen does not hold as much political power like those of the past. It's a form of government that appears to be fading with time.