Issues of local control. The planned variation aspect of "Follow Through" was thought to be beneficial—perhaps superior—to other forms of experimentation (e.g., selection of sites based on randomized assignment) because it would give local communities and schools an element of ownership integral to the successful implementation of the models. Despite the planned variation design, local communities in many sites were nevertheless deeply critical of the program. In some ways, criticism of "Follow Through" had preceded directly from Head Start. Ostensibly, the social service purpose and goals of the Head Start program were clearer than those of the "Follow Through" evaluation. Nevertheless, community leaders had felt that Head Start did not give enough decision-making responsibility to parents and community members. Local interests wanted to make curricular decisions, including the changing of facets of some program models Evans cautioned that "educational communities and contexts vary", which can have a direct effect on the implementation of a model. More problematic, however, is Elmore's and Hill's assertions that the "Follow Through" models interfered with local teaching methods and practices. As Elmore writes, "for "Follow Through", the problem was how to implement program variations in a system where most day-to-day decisions about program content are made at the school or classroom level". Rhine "et al." suggest that it is difficult to get teachers to modify their behavior. And if the objective of changing behavior is achieved, teachers feel little ownership on the model—a decidedly dubious investment. What inevitably seems to happen is that teachers reject programs outright, while others "surrender to the program".