When opening the resulting product of root manufacturing assembly, only the resulting
products of items in the session load. Selecting Load Resulting Products command to load the
resulting products of items in the session.
This allows you to load partial resulting products in a session and improves the performance
of opening although the root resulting product aggregates tons of resulting products in a
database.
Resulting products of all items load in the session when there is no selection.
Partial Loading from Manufacturing Finder
Filter PPR objects in Manufacturing Finder or Context
Builder app so that there is a fast opening for filtered objects.
The Parents/Children of Manufactured Part00000007 filters and opens in
the session.

See Customizing Preferences.