Unfortunately, Prince Charles has to sacrifice one thing before he can be eligible to rule the monarchy.

Prince Charles is currently the longest-serving heir to the throne, and he has been preparing himself to be king by having at least 600 royal engagements per year.

However, his "too political" attitude has been his biggest flaw since the beginning. In order for him to be king, a royal commentator suggested that he has to refrain himself from giving unfair opinions and getting involved in politics.

In the ITV documentary "Inside the Crown: Secrets of the Royals," royal expert Dickie Arbiter said that when Prince Charles becomes the monarch, he will need to "constitutionally keep his mouth shut."

"He has written letters to Ministers asking the sort of question that we would want an answer to," Arbiter said. "He won't be able to do that when he becomes King.

For instance, the Prince of Wales has received backlash numerous times after he broke the royal household's neutrality by having an intense connection with politicians.

Moreover, back in 1999, Prince Charles embarrassed Queen Elizabeth II after he snubbed the Chinese president on a state visit to the United Kingdom. The heir to the throne chose not to attend the state dinner held at the Chinese embassy in London as a sign of protest against China.

At that time, he supported the exiled spiritual leader of Tibet, Dalai Lama, pushing him to make such a move.

"By not attending on this occasion, he was not only letting down the monarchy, he was embarrassing his mother," Richard Kay chimed in. "Those who work for the Prince of Wales didn't have an explanation other than that he had an unbreakable arrangement elsewhere."

Meanwhile, royal expert Penny Junor seconded his opinion and added that despite that issue, Prince Charles will be the "best-prepared monarch" that the monarchy has ever had due to the time he has been spending as the heir to the throne.

Prince Charles' Plans Are "Harmful"

Even Queen Elizabeth II and Prince Philip believed that Prince Charles' plans for the monarchy will only put the royal family in danger.

In 2012, Prince Charles divulged his "future vision" to re-establish the monarchy by trimming down and shutting out wider members of the monarchy.

However, last year, a source told The Sun that during Prince Charles' "crisis meeting" with his father to talk about Prince Andrew, Prince Philip reportedly expressed his disapproval of his plans to cut out other royal members.

According to the Duke of Edinburg, modernizing the monarchy is "harmful" and Prince Charles' plan to pursue this is making him "too political."

Royal author Catherine Mayer later on supported the claims made by The Sun. She said that Queen Elizabeth II and Prince Philip memorized the precise way to "do" the monarchy. Yet, Prince Charles came to tell everyone that he wants to transform everything.

So if Prince Charles wants to be king , he should probably start changing his ways and say goodbye to his political side.

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