The Test of Prolonged Activity.
In order to be thoroughly satisfactory, observations of the effect of the changes upon the worker must be made during a long period. The worker’s greatest asset is his ability to work. In order to prove its value, fatigue eliminating work must actually show results in prolonging the years that he is able to devote to his life work. This in practice it does. Not only does the average worker remain physically able to work more years than where no fatigue elimination has taken place, but also through the fatigue study, and motion study, which he has co-operated to make, he learns to be able to teach that thing, or those things, at which he is most skilled, and thus to prolong his years of economic value. You must note how many of your workers are beyond the usual working age, and are still at work. Some of these will be working at the work itself; that is, in the performing department. Others will be planning or teaching the work in some way. The number of these and their condition will form an admirable unit of measurement of the success of your work.