Lite registers its own five-minute interval for recurring tasks. This is used, among other things, to send reminders and clean up older unconfirmed registrations.
PRO additionally uses delayed single events for waiting-list processing and checks expired offers and reservations.
Note: In standard WordPress installations, WordPress Cron is triggered by page views. On websites with very little traffic, scheduled actions may therefore run late. In such environments, using a real server cron for wp-cron.php is recommended.