Finish cycle describes the sequence of tool moves performed when doing finish cutting.
Groove To Center
The first finish move is down one edge of the groove (the right edge for OD groove)—to the bottom—and then over to the center. The next move is down the other edge, and then over to the center of the groove.
Groove To Face
The first move is down one edge of the groove—to the bottom (the left edge for OD groove). The next move is down the other edge—to the bottom—and then over to the other edge.