ES6 Array.prototype.fill() polyfill

array.prototype.fill.js

if ( ![].fill)  {
  Array.prototype.fill = function( value ) {

    var O = Object( this );
    var len = parseInt( O.length, 10 );
    var start = arguments[1];
    var relativeStart = parseInt( start, 10 ) || 0;
    var k = relativeStart < 0
            ? Math.max( len + relativeStart, 0) 
            : Math.min( relativeStart, len );
    var end = arguments[2];
    var relativeEnd = end === undefined
                      ? len 
                      : ( parseInt( end)  || 0) ;
    var final = relativeEnd < 0
                ? Math.max( len + relativeEnd, 0 )
                : Math.min( relativeEnd, len );

    for (; k < final; k++) {
        O[k] = value;
    }

    return O;
  };
}

is there a reason not to pass a radix to parseInt on line 14?