The protagonist is better loved by the readers than the author!

Many authors of well-beloved characters have grown tired of their creations but have felt bullied by their readers to keep adding new stories.  Forester's Hornblower, and Fleming's Bond are two big examples.  But Doyle's Holmes is probably the most famous and Doyle's efforts to end the series and kill-off Holmes are almost equally well-known.

Scientific American looks into the problem of killing off  a hero.

...when Arthur Conan Doyle had killed off his famous detective almost ten years earlier, in “The Final Problem,” the news was, to put it mildly, not well received. The Strand—for many years, Holmes’s home—was inundated with letters from jilted readers. Conan Doyle found himself the target of angry mail and vitriolic attacks. It’s even said that City of London clerks wore black armbands to mourn the detective’s passing. ...It’s safe to assume that on some level, Conan Doyle knew that killing Holmes may not have been the best thing for him to do. He just couldn’t help himself. “I have made up my mind to kill Sherlock Holmes; he is becoming such a burden to me that it makes my life unbearable,” he told Sir Henry Lunn

So, when is Rowling going to write the next Harry Potter?