I've seen backup jobs finish and switches show up in the front page's pie graphs as unbacked up. Digging deeper I've seen multiple cases of my team adding new network devices but forgetting to add them into multiple NCM scheduled jobs (e.g.: regularly download startup config, download running config, write memory, inventory, etc.).
I imagine more check boxes automatically showing up when adding a new device to NPM, down in the "Manage with NCM" section.
One check box for each job that's been created and enabled in NCM. Maybe an option to automatically include / enable each of those rules.