It is my impression that public institutions fail to recognize students as consumers and work to maximize potential. Ability is not one size fits all. Unless this circumstance is included in the educational equation, we will create a generation of many failures, a generation in which the disparity of income production is more pronounced than our current condition. Where lapses in parental guidance exist, public education needs to assume responsibility for, like it or not, there is no other entity capable of assuming that role. Condemnation is not a productive tool to enhance motivation.
Poor grades are a condemnation that leaves some individuals with despair.
Division by skill level is more helpful to fulfill students' potential to be productive within their means. Any employer will tell you that placing an individual in a position in which they are incapable of success ultimately destroys the individual and demoralizes the team effort. Education decision makers have designed a system for bureaucratic convenience rather than to serve the needs of the individual student and society. The incidence of student failure is not borne by the student alone. It is a systemic failure that requires the educator to sacrifice the individual to the greater student population.