Workflow is paused
Top of the automation, check the "Active / Paused" toggle. Paused workflows still log triggers but don't fire actions.
Condition filtered out
Open the run log for the relevant record. If the trigger fired but no actions ran, the condition was false. Compare the record's actual fields to the condition.
Trigger didn't fire at all
The trigger doesn't match. Example: "Record created" triggers only on creation, not on bulk import. Use "Record updated" or run the workflow manually on imported records.
Permission missing
If the action target requires a permission the automation's owner doesn't have (e.g. creating records in a module they're not enabled for), the action errors silently. Run as a user with the right permissions.