Give an assessment in the beginning or middle of a project to let the student or employee know what he can do to improve a project. This allows the person receiving the assessment time to change certain things about the project. Give an evaluation at the end of a project to tell the student or employee how the project turned out. She will be unable to change any aspect of the project at this point.
Tell the student how an assessment will help measure his learning process. Give the students advice that may help her improve her studying skills to learn the material faster. A test's results show how much the student learned or how much information she retained from a lesson; tests occur at the end of the lesson so a student cannot improve her study skills to better learn the material.
Seek areas in which the student or employee could improve. This should be an objective and subjective assessment of progress at a given time. Give an evaluation on a later date to tell the student or employee if the areas you mentioned could improve, actually did.