Meghan Markle's eager comment in an interview while engaged to Prince Harry caused "shudders at the Palace", a royal expert has said.
Months before her wedding to Harry, Meghan along with the Duke and Duchess of Cambridge held the Royal Foundation's first forum event.
At the event, the two couples talked about the charity foundation and its plans for the future.
The foundation was set up by Prince William, Kate and Harry with Meghan joining them and speaking at the event in February 2018.
During the forum, she remarked how she was keen to "hit the ground running" when it came to working with royal charities.
However, according to The Telegraph, in her new book The Palace Papers, royal author Tina Brown recalls that Meghan's comment caused "shudders at the Palace", where things work a lot slower.
In an interview with the newspaper, Ms Brown, a former editor of Vanity Fair who was friends with Princess Diana, said: "I think Meghan felt she could get in there and change it all.
"Frankly, she could have done a great deal to change things had she stuck around, but the thing that’s most baffling is such impatience. She could have spent a year away and come back with a great game plan."
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Just under two years after that event, it was announced that Meghan and Harry were stepping back from royal duties to carve out a new life together in the US.
And it's noted that Meghan gave royal duty 20 months, while Ms Brown added: "Diana gave it 16 years."
Ms Brown's new book, The Palace Papers is set to be released later this month.
The publisher claims it will tell the "real story" of the royals since Diana's death in 1997 - and is "full of nuanced details and searing insight".
It also adds that the author developed the book from her "years of research" and "intimate access" to the royals and will chart the Queen's "loosening grip" on the Firm.
Meanwhile, it has been reported that Meghan will embark on her first trip outside of the US since she quit the royal family by travelling with Harry to the Invictus Game s in Holland this week.
The Mirror revealed on Saturday that Harry and Meghan will be followed by a Netflix documentary crew throughout the Games, which start on Saturday.
The couple’s decision to attend the event in The Hague has been blasted by palace insiders after Harry claimed it was “too dangerous” to travel to the UK.
He is locked in a legal battle with the UK government over a decision to downgrade his security and did not show up at a memorial service for his grandfather, Prince Philip, last month.
