It appear that a trigger campaign did not process a lead when the trigger occurred.
- Lead has not qualified before
- Lead satisfies all filters
- Campaign results do not show any evidence of the lead being processed
The reason why it appears that the campaign did not trigger may be because there is currently a campaign backlog. There is a campaign or multiple campaigns with leads pending to be processed. This can be viewed in Marketing Activities [select the top level item 'Marketing Activities' on the navigation tree on the left > select Campaign Queue tab]
The lead will be processed eventually once the campaign backlog clears.