Old sketchbooks are often left in a dark cabinet, helping only to sustain the local population of silverfish. But they contain endless training benefits for improving your skills and vision. Reviewing older work to note strengths and weaknesses, you can help improve future work. Reviewing this sketch from a few years ago, I see an improper neck angle, uneven texture levels (eyes lack crisp detail and focus), and some balance problems with the weight of the face. Reviewing a sketch even day or two later can give you a renewed direction.