"Destroy my manuscripts"

Just before Frank Kafka died he asked his friend to destroy all his manuscripts. His friend didn't. So we have the pleasure - or otherwise - of reading Kafka's works. "The Trial" is his most famous work, a novel about a man who is one day arrested but he doesn't know why. It's a strange book, later made into a film by Orson Welles, one of his lesser known films which never was popular.
Philip Larkin asked his biographer to destroy all his letters after he died. I am told that he did.
I'm not sure if it is a good thing to carry out the orders of great writers who demand such things as destroying their manuscripts and letters; maybe they are not in their right minds when they are about to die.
John Murray, the publisher, made a fortune by publishing Lord Byron's "Childe Harold" but when Byron offered him his autobiography Murray not only did not publish it but, since by then Byron had died abroad, accidentally drowning, felt it would not be beneficial to Byron's reputation so he burned it.
I read about this on the weekend, then oddly, yesterday I read something about Thomas Moore, an Irish poet who knew Byron; apparently he too was given a copy of Byron's autobiography by Byron himself and he too destroyed it. Two autobiographies by the same man given to two people both of whom burned them!
A friend of mine who is a good poet and used to write short stories and novels, none published, decided in his 70's that all his fiction was no good so he destroyed it all.
"Did you burn it?" I asked him.
"No, I put it to some good use," he said. "I put it in the trench ready for my kidney beans."
"Good crop?" I asked.
"One of the best I've ever had," he said.