A major disadvantage of essay tests is their inherent scoring subjectivity. Unlike objective item types where there is a single correct answer, essay responses are open-ended and require human judgment for evaluation. This subjectivity can lead to inconsistencies in grading, meaning different graders might assign different scores to the same essay, or even the same grader might score an essay differently at various times.
Factors contributing to this subjectivity include the absence of clear, detailed rubrics, the influence of extraneous elements like handwriting or grammar, and unconscious biases of the grader. While efforts like using detailed rubrics, blind grading, or multiple graders can mitigate this issue, it remains a significant challenge. This lack of consistent, objective scoring can compromise the reliability and fairness of the assessment, making it difficult to compare student performance accurately across different tests or cohorts.