To illustrate the impact of forecasting on stocks and order quantity, assume that it takes 3 periods before an order will be received. This needs to be taken into account when placing an order. The below figure shows actual demand compared with the order quantity based on MA and ES demand forecasts. As can be seen clearly the fluctuation in demand is amplified in the orders, illustrating the bullwhip effect.
The amplification for the ES forecasts is about twice the amplification from the MA demands. So although SE gives better forecasts it amplifies the fluctuations in the demand more than the simple MA forecasting method in this case. Not something you would expect. When comparing net stock with actual demand a similar picture arises.