Low expectations are much worse than high expectations. Low expectations are a recipe for low performance. For a principal, low expectations remove the need for results. For a teacher, it is an invitation to ease up and allow a certain percentage of hard-to-teach students to fail; and students always do better when teachers really try. Motivation is important in any human endeavor, and that includes teaching. What gets inspected gets respected. Reasonable accountability systems, applied humanely, give the public useful information about the performance of schools without harming children in the process. In its present form, NCLB is not that system.
Day, Richard E., "Lowering State's Educatioon Standards A Bad Idea" (2007). Curriculum and Instruction Faculty and Staff Scholarship. Paper 47.