From the Painting Guide: These are both very tender and humanistic portraits. The seated figure is well captured, but take another look at where her arm/hand rests on her knee and then the angle at which that leg comes up from the ankle. The ankle also looks too broad/wide, which makes the rest of the foot seem too big. The background of this painting has structures and forms which are hinted at but which become disjoined. For example, the top of the box-shape by her legs merges with the verticals.

Things to consider:
• Colours: In the second painting, which is dominated by cool colours, the warm red of the stool draws in the viewer's eye very strongly. Creating a greater contrast between the background and skin tones and removing the warmth from seat would to direct the viewer's eye to the figure itself. In the first painting, the background tones around the head are very close to those of the jacket, which makes the face stand out. If the intention was for the jacket to merge with the background, so that the emphasis is solely on the face, then it needs to merge a bit more.
• Working from photographs: The first painting is rather two-dimensional, the features seem flat rather than curving around the face. I may be wrong, but I'm presuming that photos were used as reference for these portraits, which may be where this problem originates as photos are already a two-dimensional representation of a three-dimensional object. Using several photos rather than just one, and having observed the person/object, will help with the recreation of the three-dimensionality (see also these articles: Painting from Photos and How to Take Reference Photos).