The deblank function eliminates only trailing blanks from the string, not leading the blanks. The strtrim function will eliminate both the leading and trailing blanks from a string, but not blanks in a middle of the string. In the illustration below, the three blanks in the starting and four blanks in the end are eliminated, but not the two blanks in the middle. Choosing the result in MATLAB with the mouse would show the blank spaces.
>> strvar = [blanks(3) 'xx' blanks(2) 'yy' blanks(4)]