Progress table is not update even progress is 100% completed

It seems that if the time takes to complete between the last 2 batches are very close, it will update the progress table even is the batch is 100% completed.

function progress_set_intervalled_progress($name, $message, $progress, $interval = NULL) {
  static $set = array();
  if (isset($interval, $set[$name])) {
    if ($set[$name] + $interval > microtime(TRUE)) {
      return TRUE;
    }
  }
  $result = progress_set_progress($name, $message, $progress);
  $set[$name] = microtime(TRUE);
  return $result;
}