To increase user engagement, and save Admins some time, you can set up automatic weekly reminder emails to uncompliant end users. You will find this under Tools>Notification>Alerts.
This will result in the content notification email going out to end users once a week for the number of alerts you have set up:
You can then select which Admins are to receive an uncompliant user report email showing those users who have received the maximum number of alerts, but who have still not as yet completed the content.
Related Articles:
How Can I Edit My Email Templates?
How Can I Switch On Email Reminders?