I don't understand why they even try, Debian stable seem to have an almost arbitrary selection of outdated ruby and python libraries, at this point that hardly seems worth the effort. Sure I get the idea, but it obviously doesn't work in practice.
Their security methodology also seems heavily flawed, to backport security fixes to older versions is neither scalable nor particularly reliable. I sincerely doubt that Debian can provide adequate security to its almost 50,000 packages. If the security community would invest equal amount of resources that they invest in finding flaws in iOS or Chrome, nothing would be left of Debian but a pile of smoking ashes.