Scenario:
An Event was created by an Organizer. The Event shows up in other user's Calendar but not in the Organizer's Calendar .
Solution:
In order for an Event to show up in a user's Calendar, the user should be included in the list of attendees for the said Event. The creator of the event is automatically included by default as an Attendee. But there are certain instances wherein Organizers are removed by means of editing an existing event or was unintentionally removed through scripts deployed in the Event Record. If this is the case, user do not see the event in their own Calendar.