There is currently a situation where it is possible for a document to lose its effective date. This can occur when an Approved, Not Effective (effective date set in the future) document that has been processed through the Document Change Control Process is modified using the "Modify Metadata Only" functionality.
In this specific situation, the modify page will load and the effective date will default to "Set Through DOC Process" even if a value was already attributed to it.
If the user submits the modifications without changing the effective date to the appropriate value, it will revert to "Set Through DOC Process" and lose the current date value, leading to the document never ending up being made effective, unless the effective date is modified again.
It is therefore recommended to review any modifications and pay special attention to the effective date field before submitting changes via Modify Metadata Only after a document has already been approved.