why it is needed to include the MIG-Work packet to the latest MSI?

When an MSI is created prior to migration of the MIG Workpacket
already checked-in, a new MSI should be created and should
ensure that the MIG Workpacket checked-in has been migrated
to BLD environment first
before running the MSI creation tool.

the question is, why it is important to include the MIG workpacket
to the latest MSI?

i’ll appreaciate your answer. thank you.