I think it has to do with flying the missed approach procedure for the the initial Instrument Approach.
For example at Dublin
Flying the VOR approach to 16 for a circle to land at 34
We set the minimas for 16 as this was the approach we flew and it will be the go around procedure we follow at any stage during the procedure.
The go around for 16 is climb on track 155 degrees to Killiney climbing 3000feet
Whereas the go around for 34 is climb straight ahead to 3000 and contact ATC
So even if we are at 300 feet on finals to 34 and ATC say go around we must follow the procedure for RW 16 which is climb turn and track 155 to killiney.
I know at dublin the circle to land MDAs for 16 and 34 are the same but maybe this might help
I hope I understood ur question right.