The shaft determines how powerfully and accurately the shuttle can be struck with the frame head. Shafts with more rigidity are more unforgiving, and you should use them only if you are an advanced player, who can generate good power with a little swing of the racket. And because of their rigidity, they are also very accurate. They do not flex so much as to make deviations from the intended path of the racket head. Flexible shafts, on the other hand, are good for beginner and intermediate players who don’t have explosive power in their hands yet. Flexible shafts allow a bigger bat swing, building up power and delivering it using the whipping action. For the same reason, they may be assumed to be easier on the wrist and other joints of the player. Flexible shafts, however, produce a delay or a lag in the movement of the racket head which makes it somewhat inaccurate, compared to the stiff shaft. Also, the flexibility and stiffness are not just along the length of the shaft, but they also apply torsionally, around the circumference of the shaft, that is. Therefore, sudden changes in direction of the handle are communicated well by a stiffer handle than a more flexible handle.