Why did Sir Arthur Conan Doyle "kill" Sherlock Holmes?

''Killing'' Sherlock was a way out to stop writing about him! Doyle appreciated much more his history&sci-fi novels than all the stories about Holmes, so he tried again and again to get rid of this character. But under the influence of his publishers and readers he had to bring Sherlock back to life every time he ''killed'' him.
Even now, there are few persons who know about other Conan Doyle's novels, but almost everybody know about Sherlock Holmes!

"It was not murder, but homocide in self defense; for if i did not kill him, he most certainly would have killed me"

he killed off sherlock holmes to start righting other books but due to popular demand he had to bring sherlock holmes back