Why did J.K. Rowling write under a pseudonym? 'Just for the joy of it'

Any news about J.K. Rowling and her books is guaranteed to make headlines around the world.

So when it broke that not only had Rowling written another book but that readers could already find it in stores as well as in e-book format, the novel shot to the top of bestseller lists as rapidly as it disappeared from bookshop shelves. How'd the public miss it? Rowling had released her novel, "The Cuckoo's Calling," under the pseudonym Robert Galbraith (described as a former member of the Royal Military Police).

"I had hoped to keep this secret a little longer," Rowling said in a statement. “Being Robert Galbraith has been such a liberating experience. It has been wonderful to publish without hype or expectation, and pure pleasure to get feedback under a different name."

She also thanked "the writers and reviewers, both in the newspapers and online, who have been so generous to the novel."

It all made sense to horror writer Stephen King. King, who has also written under a pseudonym (he published short stories under the name Richard Bachman until Bachman's real identity was discovered), told USA Today he understood why the "Harry Potter" author would want to publish something under a new name.

"Jo is right about one big thing – what a pleasure, what a blessed relief, to write in anonymity, just for the joy of it," he said. "Now that I know, I can't wait to read the book."

Although sales of Rowling's book lagged, reviews were effusive even before the actual author was discovered, with Publishers Weekly calling it a "stellar" debut and Library Journal writing that "Galbraith's take on contemporary celebrity obsession makes for a grand beach read. It's like a mash-up of Charles Dickens and Penny Vincenzi."

Crime writer Mark Billingham wrote it was "hard to believe this is a debut novel."

Amazon editorial director Sara Nelson said she admired what Rowling had done, seeming to want to receive honest criticism separate from the attention her name now inevitably brings.

"She wants to write," Nelson said of the author. "She just wants to work."

In addition, Nelson said she found the story unusual.

"Historically, writers have used a different name when they're going to write a different kind of book," she noted. Rowling's novel is a different genre from her normal fare, but that doesn't seem to be the reason she chose a pseudonym.

As for what publisher Little, Brown thought when it released a novel by a superstar under a false name, Nelson said she thinks both the publisher and Rowling knew the truth wouldn't stay buried.

"In this world, everyone knows nothing stays a secret forever," she said.

Will we now see a rash of novels released under pen names? Nelson doesn't think so.

"I don't think it's a trend," she said, noting that she thinks authors will continue to do it if they want to try a different genre, like "if John Grisham wanted to write a romance novel."

But Nelson thinks the success of "The Cuckoo's Calling" may prove enduring.

"If the word-of-mouth on this is good, and there'll be [more] reviews now.... I think this might have legs," she said.