Newsstand's promise is that it would automatically update in the background overnight any newspapers and magazines or other periodicals that need such updates. Great concept but flawed in practice. One of Apple's many recent software features that 'just don't work'.
I subscribe to many apps that live in the Newsstand folder and I've allowed everything to update automatically via the Settings app. However, almost none of my apps every actually get new content overnight and are waiting for me to consume in the morning. While New York Times app is the worst offender, none of the others - The New Yorker or the National Geographic or the Magazine app ever get updated consistently if at all.
It is hard to know where the problem is. Is it with Apple's framework or with the apps themselves? Almost no app updating correctly points to a problem with the framework.
Seriously believe that it is not Android but decline in Apple's software quality is the single biggest threat to the company.