PO Trouble -- no item to select

    When we created a po line, the item list contained nothing.
    We checked the item's attributes, and the purchasable flag was correct. i looked up the reason in the Oracle Purchase Manual, and i found it! --

Purchasing can create shipments only when it has default information
that meets the following criteria:
• There must be an organization and a location.
• The location must belong to the organization or not be assigned
to any organization.
• If the line contains an item (and optionally a revision), that item
(and revision) must be valid in the default shipment
organization.

    The location's assignment is multiple.

     

   
    
    But, is it the true reason?