docs: protected <T extends Enum<T>> OperationObserver<T> createObserver(String name, Class<T> outcome, boolean canBeDisabled) {
      if(!operationStatisticsEnabled && canBeDisabled) {
        return ZeroOperationStatistic.get();
      }
      return operation(outcome).named(name).of(this).tag(getStatisticsTag()).build();
    }