From the COBOL Language Reference
5.3.9 JUSTIFIED clause
The JUSTIFIED clause overrides standard positioning rules for receiving items of category alphabetic, alphanumeric, DBCS, or national.
These variables are left justified by default (unlike numeric variables, which are justified to the decimal point either actually specified in the PIC or implied). If you have variable X defined as PIC X(5) and move 'AB' to it, the actual value in X is AB<B><B><B> where <B> represents a blank (space) character. With PIC X(5) JUST RIGHT, the value would be stored as <B><B><B>AB.