We recently found that an application was being published & its configured MST was missing, the failure was in the PMPC logs but the publishing notification email stated it was successful with no errors.
We have a specific OH&S business requirement where this application is customised to include our tenant information etc & if the transforms is not applied, critical OH&S information is not reported and recorded.
Publishing actions should include error notification on missing MST's when publishing and/or allow us to configure "error levels" for the existing soft failures, giving us the ability to force fail an attempted application / software update publish if all configurations were unable to be included in published artifact
This will be fixed in the next preview release.
This is actually a bug. It should have been failing to publish. It only occurred for Intune apps and updates.