The Original of Laura, the last novel of Vladimir Nabokov, was published last week. Normally, a new novel doesn't get a lot of media attention but this one's a little different: Nabokov didn't want it to be published. In fact, he wanted it burned.
It was in his last will and testament that all unfinished works of his should be destroyed. When Nabokov died in 1977, his family didn't carry out this wish. They were emotionally distraught and procrastinated the decision, putting the work in a bank vault. For thirty years, a battle of what The Times called "the demands of the literary world versus the posthumous rights of an author over his art" worn on. Eventually, the literary world won...sort of. The novel, apparently, isn't very good (at least in the state it's in).
According to the author's son, destroying the manuscript was something he never seriously considered. Such an attitude makes me nervous; not only did his son fail to follow an aspect of his last will and testament (as did his wife, who died in 1991), it has the potential to shrink the number of good novels.
Nabokov, like many writers, clearly didn't want works published that fail to live up their standards: even after death (the idea that you leave a part of yourself behind after you die is, I'm sure, a motivation for many writers). Suppose the standard attitude of posthumous publishing becomes "ignore last requests and publish anyway." I guarantee you, some aging authors will be less willing to even start a novel in fear that they won't be able to complete it before their death, even if it turns out they could. This can cost the literary world something very valuable. While suffering from tuberculosis, and certainly concerned he might die soon, Orwell worked on 1984, which was only published a year before his death. Mark Twain, Jane Austen, Charles Dickens, and Jules Verne (to name a few) also published several works near the end of their lives.