Moderate Skill Acquired in the Ordinary Day's Work Merely repeating a performance many times does not give the high degree of skill that we see in the expert telegrapher or typist. Ordinarily, we practise much less assiduously, are much less zealous, and have no such perfect measure of the success of our work. For "practice to make perfect", it must be strongly motivated, and it must be sharply checked up by some index or measure of success or failure. If the success of a performance can be measured, and chalked up before the learner's eyes in the form of a practice curve, so that he can see his progress, this acts as a strong incentive to rapid improvement. Ordinarily, we have no clear indication of exactly how well we are doing, and are satisfied if we get through our job easily and without too much criticism and ridicule from people around. Consequently we reach only a moderate degree of skill, nowhere near the physiological limit, and do not acquire the methods of the real expert. This is very true of the manual worker. Typesetters of ten or more years' experience were once selected as subjects for an experiment on the effects of alcohol, because it was assumed that they must have already reached their maximum skill. In regard to alcohol, the result was that this drug caused a falling off in speed and accuracy of work--but that is another story. What we are interested in here is the fact that, as soon as these long-practised operators found themselves under observation, and their work measured, they all began to improve and in the course of a couple of weeks {327} reached quite a new level of performance. Their former level had been reasonably satisfactory under workaday conditions, and special incentive was needed to make them approach their limit. A similar condition of affairs has been disclosed by "motion studies" in many kinds of manual work; the movements of the operative have been photographed or closely examined by the efficiency expert, and analyzed to determine whether there are any superfluous movements that could be eliminated, and whether a different method of work would be economical of time and effort. Usually, superfluous motion has been found and considerable economy seen to be possible. There is evidently no law of learning to the effect that continued repetition of a performance necessarily makes it perfect in speed, ease, or adaptation to the task in hand. What the manual worker attains as the result of prolonged experience is a passable performance, but not at all the maximum of skill.