Outside Operation Cost in Part Cost

Greetings to all! :)

To include the Cost from the OutsideOperationItem (purchased part) used for Outside Operation we must manually enter a value in the column "unit cost" in the  view Outside Operation Cost.  

When it is not entered in the view Outside Operation Cost - it is not included in the Part Cost Calculation for the Main Part where the Outside Operation ITEM is included in the routing.  

We have the cost for this Outside Operation item in the Purchase Part (Supplier for Purchase Part),  

Why do we have to enter the value again in outside operation cost? 

Can this be automized?

Event?

Or is some basic data/connection in the costing missing?  

Thank you in advance,

/F