For JES2, on the DD, OUTPUT JCL, or /*OUTPUT statement: if you do not code a COPIES parameter, code it incorrectly, or code COPIES=0, the system uses a default of 1, which is the default for the DD COPIES parameter.

For JES3, on the DD, OUTPUT JCL, or //*FORMAT statement: if you do not code a COPIES parameter, code it incorrectly, or code COPIES=0 on the DD statement, the system uses a default of 1, which is the default for the DD COPIES parameter.