The Standard program design is designed to propose the last used order type as this may be , in many cases, also the desired order type for the new
order(Process/production). This can be changed manually or removed completely.
If you do not specify any order type when you create a process/production order on the initial screen, the system will try to determine these from the
production scheduling profile defined in the material master (either directly or via the production scheduler).
Since automatic determination does not occur if an order type is already defaulted on the initial screen while creating process/production order. It is desired that no order type is proposed from last used order type so that it determines automatically.
If you wish to enable this and change the standard program behaviour then necessary modifications mentioned in SAP Note 576556 – Process order
creation: Order type default value and SAP Note 519888 – Order type for the creation of production order are to be done.(Valid till Enhancement package 6 for SAP ECC ).
Please do check SAP note170183 before applying these modifications.