NetworkManager was written to make wireless & laptop use easier _immediately_, and server & immobile workstation cases would be dealt with at a slightly later date. The current operation of NM is entirely consistent with a laptop/mobile-user use-case, and I've not heard [m]any of these users complain. Laptop & mobile users do not always have network. So in the current system, cronjobs have no guarantee of being run either. NM doesn't change that.