We know that good writing usually takes multiple drafts, buta recent study in the journal Research in the Teaching of English suggests that even though students routinely use word processing software that has the potential to facilitate global revision, much of students’ “revisions” remain at the sentence or word level.  Simply asking students to produce multiple drafts, therefore, may not lead to significantly better writing.  Instead, students need to be taught how to make global revisions, perhaps with a new assignment or set of directions to guide them in moving from one draft to the next.

[Dave, A. M., & Russell, D. R. (2010). Drafting and Revision Using Word Processing by Undergraduate Student Writers: Changing Conceptions and Practices. Research in the Teaching of English 44.4. 406-434.]