About Triggers

Triggers can be set up so that they execute automatically or as specified by users. When used with transition types that automatically link items (Copy, Post, Subtask, and External Post), triggers can fire without any intervention. You can also create triggers that users manually activate when they create a link between two items.

Triggers are created in the Global Process App and referenced from the process app from which you want the trigger to fire. They can be used to:
Triggers will fail when enabled for transitions that have unspecified values for required fields. For best results, provide default values for fields that are set as required for transitions in which triggers are enabled.