Malvin Tumin presented a comprehensive criticism of Davis and Moore's theory. He begins by questioning the adequacy of their measurement of the functional importance of positions. Davis and Moore had tended to assume that the most highly rewarded positions are indeed the most important. However many occupations which afford little prestige or economic reward can be seen as vital to society. Tumin argues that Davis and Moore have ignored the influence of power on the unequal distribution of rewards. Thus differences in pay of differences in their power rather than their functional importance .For example the difference between the wages of farm laborers and coal miners can be interpreted as a result of the bargaining power of the two groups.
Davis and Moore assume that only a limited number of individuals have the talent to acquire the skills necessary for the functionally most important positions. Tumin regards this as a very questionable assumption. Firstly an effective method of measuring talent and ability has yet to be devised. Secondly there is no proof that exceptional talents are required for that position which Davis and Moore consider important. Thirdly the pool of talent in society may be considerably larger than Davis and Moore assume. As a result unequal rewards may not be necessary to harness it. Tumin also questions the view that the training required for important position should be regarded as sacrifice and therefore in need of compensation. He points to the rewards of being student leisure, freedom and the opportunity for self-development he notes that any loss of earnings and usually be made up during the first ten years of work. Differential rewards during this period may be justified. However Tumin sees no reason for continuing this compensation for the rest of an individuals working life.
According to Davis and Moore the major function of unequal rewards is to motivate talented individuals and allocate them to the functionally most important positions. Tumin reject this view, he argues that social stratification can and often does act as a barrier to the motivation and recruitment of talent. This is apparent in closed system such as caste and racial stratification thus the ascribed status of untouchables prevented even the most talented from becoming Brahmins. Tumin suggests that even relatively open systems of stratification erect barriers to the motivation and recruitment of talent. There is considerable evidence to suggest that the class system in western industrial society limits the possibility of the discovery and utilization of talent. In general the lower an individual's class position the more likely he is to leave school at the minimum leaving age and he less likely to aspire and strive for a highly rewarded position. Thus the motivation to succeed is unequally distributed throughout the class system. As a result social class can act as an obstacle to the motivation of talent. Tumin concludes that stratification by its very nature can never adequately perform the functions that Davis and Moore assign to in. He argues that those born into the lower strata can never have those same opportunities for realizing their talents as those born in to higher strata.
Tumin maintains that it is only when there is a generally equal access to recruitment and training for all potentially talented persons that differential rewards can conceivable be justified as functional. Finally Tumin questions the view that social stratification functions to integrate the social system. He argues that rewards can encourage hostility, suspicion and distrust among the various segments of a society. Stratification is divisive rather than an integrating force and it can weaken social integration by giving members of the lower strata a feeling of being excluded from participation in the large society. This is particularly apparent in systems of racial stratification.