I find the post-mortems helpful. I don't want to make the same mistakes with my infrastructure, and it gives me something to reference when, for instance, the upper management decides they want to migrate to one of these services.
That seems at least partially true. However, I suspect that people would continue to think highly of tech companies that posted post-mortems, even if the issues were hitherto unknown. Ie, maybe it isn't only an act to prove that 'we are still trustworthy and transparent,' but also somewhat positive in and of itself?
