Thoughts on Posthumous Publishing

When is it acceptable to publish an author's unpublished work when they're gone? And when is it disrespectful to their memory, or to the integrity of the work itself?

With the new release of Gabriel García Marquez's posthumously published work, Until August, it's time to consider the ups and downs and ins and outs of posthumous publishing. For instance, when is it appropriate to publish a posthumous work and when is it not? And at what point is an author's work no longer theirs after its edited without their knowledge or final consent?