In the Haber process, the best yield of ammonia is produced at a low temperature. Explain why

The forward reaction, N_{2 (g)}+ 3H_2(g) --->  2NH3(g) is an exothermic reaction. This means that energy is released to the surroundings during the reaction and the reaction has a negative enthalpy change. Using equilibrium laws, when the temperature is decreased, the system will shift to opose this change. This means that the equilibrium will shift to favour the exothermic reaction, so therefore will shift right to increase the yield of ammonia at a low temperature.