One critical element of Yoga practice is the ability to focus energy to different parts of the body. Ancient sages could stop their heart beating, or even stop breathing for long periods of time simply to demonstrate their ability to focus and maintain that focus in finite detail. In our Yoga practice we learn to focus on those areas of our body that are stiff or blocked. This is a vital part of Yoga practice, one which is often overlooked in the search for more quantity rather than quality.
Approaching postures as goals is helpful for progress but can make people less sensitive to the messages the body is sending. If you are continually focussed on where you want to be rather than where you are, it breeds an attitude of ungratefulness and a state of tension.
The body has its own pace for opening and developing. Going too fast or too slow are both mindsets which, no doubt, reflect the cause of stress in many other areas of life.
The evaluation of progress is a very ingrained part of our social structure. Schooling, sports and work systems all value progress so it is quite a contradiction when, in midst of all this, Yoga infers something quite different. Progress in Yoga is the ability to be right where we are, and in being there finding the gratitude and thankfulness for what is. Progress is the ability to be who we are and appreciate what we have exactly as it is. Yoga offers a deeper way of measuring who and what we are.
It is easy to get caught up in the complexity or difficulty of the practice you perform. When you translate Yoga into a performance-based system it can give a sense of worth. This level of self-worth is unfortunately transient and is a detour on the path to personal growth. The role of the teacher in this situation is to help the student recognise this confusion and return to a more real state of constancy of practice.