I used to have piles of magazines that I hadn't placed. They tried getting us to put them through the doors of not at homes and count them as placements but I didn't feel honest doing that so they got recycled.
We placed very little literature, some mags did better than others and i don't believe for a second that they are the most widely read magazine, not with the amount of publishers I knew that felt guilty for recycling their piles of them but did it anyway.