The Department of Defense Electronic Reading Room publishes the decisions of the Corrections of Discharge Review Boards (DRB) and the Boards for Correction of Military/Naval Records (BCMR) at a public website. You can go to the website below and read decisions from each of the services to get an idea of what an applicant stated with regard to the error or injustice in his or her case as well as the Board's rationale for granting or denying the request.
Coastguardsman's application to the Coast Guard Discharge Review Board--Why his case was denied
https://boards.law.af.mil/index.htm