The antonyms for the term "feasibility studies" are impracticality, infeasibility, impossibility, unfeasibility, and impracticability. These words connote a lack of possibility, viability, practicability, or achievability when it comes to conducting a systematic analysis of a project or a business proposition. In particular, infeasibility and unfeasibility refer to ideas or ventures that cannot be implemented or carried out, either due to financial constraints, technological limitations, or social and environmental concerns. Impracticability, meanwhile, suggests that a certain task or undertaking is challenging or unworkable to execute or achieve. In contrast, feasibility studies aim to evaluate the potential or capacity of a project to fulfill its objectives, identify its strengths and limitations, and provide recommendations for its implementation.