"Form" does have many uses. I refer to the drawing structure, the accurateness of your line work, not the form of the figure (or of IRS, or any other form of form.)
The outlines or edges of the faces in the first post are a little skewed, which, in these angles of the face, are very critical indeed. The slightest missed line is more obvious in these views. Thus are the joys and pains of portrait drawing!