No, that is not true. Monarchs are human; some are outright bad. The benefit of monarchy is that whatever kind the monarch is, he has the natural interest in protecting his property, which in his case is the national infrastructure, while annoying the least amount of people possible. Unlike an elected politician he has no interest in squandering it or lie to us on a 4-year cycle.
But on the other hand, if hte monarch is irresponsible, innocents suffer. Nicholas II was a perfect husband and good father, BUT a failure of a monarch and it cost millions of Russians their lives in the Russo-Japanese War, then WWI. Nicholas mismanaged both and millions lost their lives.
BINGO! The Culture, Institutions, Big "G" Government (the Government its self not the department of economic planing and cheese welfare)are there to be maintained, not the Looting that we fight back every election cycle in this country, "who can steal the most from someone Else and give it to me"
Now, this does NOT mean that a Monarch can't be corrupt or bad, this does not mean the Monarchy itself is corrupt or Bad, King John shouldn't taint the reputation of Queen Elizabeth II, just for the fact that they were both Monarchs of England.
P.S. Thank you for the Links, This Serbian Student makes a brief, but very good argument for the restoration of the Monarchy in Serbia.