Everyone has seen flailing fingers playing lots of high notes fast. One of the goals of good scale technique is to maximize left hand accuracy and speed by minimizing extraneous finger motion. Disciplined fingers can move in any direction on the neck, stay directly over the strings and not stray further than 1/2 inch above the strings.

Ex. 1 a-c are deceptively simple, but they are FUNDAMENTAL to achieving good scale technique. Intense concentration is necessary to produce desired results. Focus on: 1) only applying pressure to the finger that is playing, 2)uninvolved fingers toward the soundhole (i.e. 3 & 4 in Ex. 1c) should hover motionless <1/2 inch in position above the string, and 3)uninvolved fingers toward the nutt (i.e. 1 & 2 in Ex. 1a) should rest gently (9th and 10th fret, respectively)on the string.

Caveats: 1) Unless you apply this level of disciplined effort, you will be wasting your time with these exercises. 2) Seek instruction from a competent guitar teacher to insure your thumb and finger placement are correct.