Answer to Question 1
Answer: Scientific management was largely developed by Frederick W. Taylor and summarized in his 1911 book Principles of Scientific Management. Taylor and the other proponents of scientific management observed workers on the job and assessed their performance.
Taylor felt that job performance of workers generally lacked uniformity, and rather than perform the task in the best way possible, workers were apt to use sloppy, ineffective, or inefficient techniques. Accordingly, Taylor developed the idea of the one best way to perform a job that maintained that managers should (a) identify the best possible manner in which a task could be performed and (b) require that workers use this method on the job.
Answer to Question 2
Answer: In Wealth of Nations, Adam Smith argued, among other things, that the division of labor that took place in factories in which large, complex job tasks were broken down into small, repetitive actions would result in dramatic increases in productivity. This productivity would, in turn, bring new wealth to the countries that could employ this system of production.
Smith's prediction turned out to be only partly true as division of labor was discovered to have drawbacks. Though division of labor initially increased productivity, that increase tended to fade as workers, bogged down in repetitive tasks, lost morale and motivation to put out maximum effort.