Do you mean an Email Program? Because this is the only type of Program that can be 'Unapproved'. Engagement Programs can be turned off, and for Event and Default Programs do you mean based on de-activation of all Smart Campaigns?
We just had a situation happen where an email program we had scheduled and approved timed out during processing because Marketo couldn't work through the smart list logic we had created (we referenced other smart lists). As a result, the email was not sent out and the program was unapproved. There was no notification that the problem had occurred, so we didn't see it until days after it was supposed to have been sent. This notification would have alerted us right away that something was wrong. It seems there should be a notification any time something times out, but the un-approve notification would have helped.
*Correction: Marketo did not un-approve the asset. So this would actually not have helped us. We would need a notification of the error itself. I've created a separate Idea for this:
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