If the departure has been transfered directly from the tower the code may not have been verified, (not all towers have SSR monitors).On certain ocassions SSR at an airfield may be out of service.
Our manual at Scottish still insists that we must ensure that the correct data block is assigned to the correct squawk allocation.
It has happened in the past that squawk allocation have been transposed and it has caused all sort of fun and games.
I believe there have been some moves afoot to try and change operating procs,however the system we use is over 25years old so I think a change is unlikely.
Perhaps things will change when we move into The New Scottish
Centre.
Rgds
AyrTC