Customer created an e-mail policy to send e-mail alerts every time some specific tasks fail to complete. It was working for all selected tasks (create user, change password, request access, etc.) except for a custom Modify User task. The task was failing to complete but no e-mail was sent. Nothing available on the logs, even in debug.
The task synchronization options were preventing the e-mail to be sent.
Identity Manager r12.6 SP8 (but this problem was seen in earlier releases prior to the upgrade)
All tasks that were sending the e-mail in case of the task failed to complete had the Account Synchronization option set to "On every event", but the custom Modify User task had it set to "On task completion". After changing the Account Synchronization option to happen on every event (matching the other tasks) the e-mail was sent when the task failed to complete.
To change the Account Synchronization option, please do the following:
Test again and you will see the e-mail being sent for the failed task.