Be honest and acknowledge the limitations of your study. The manuscript is poorly organized . This can be avoided by beginning with an outline or some other organizational plan. The topic is irrelevant . The manuscript is poorly written.
Writing is hard work, but it is a skill that can be learned.
The study is poorly designed. Unless the study can be revised and repeated, the written report of a poorly designed study is not correctable. The data are poorly handled. In some cases, data can be reanalyzed using more appropriate methods and the rewritten manuscript can then be resubmitted. The data are insufficient.