Modify the Participants column in the Event Summary table on the CiviEvent dashboard (civicrm/event?reset=1) to show count of both registered and pending status participants:
Registered: 12 (show)
Pending: 5 (show)
— original post —
not sure if this is intended behaviour
When a client has registered and checked 'Pay later' the status of the registration goes to 'pending'. The registration doesn't show up in the event list which might confuse the organizers to the amount of people showing up (but payment still pending). Since te status is already shown when the complete list is shown it might be better to include also the 'pending' status.