Under what circumstances the STEPControl_Writer.Transfer() will fail or success ?

I have some confusion with STEPControl_Writer.Transfer():
What conditions should the TopoDS_Shape to meet can transfer succeed?

I meet two situations:
1) I create a bottle follow the tutorial, it transfer succeed and can output as a step file right.

2)when I get a face from step file, I want to output the TopoDS_Shape of this face as a step file, and transfer fail.

So, I'm confusing why the Transfer() fail in situation 2; should I rebuild topology like "point->edge->wire->face" for the face I get from a exit 3d model ?