The German Army placed a high reliance on mortars. As the British official historian, L.F. Ellis, states, "In the latter stages of the war German interest in conventional field and medium artillery seems to have been on the wane. Instead they were setting more store by mortars and nebelwerfers, of which they had large numbers in Normandy." (L.F. Ellis, Victory in the West Volume I, The Battle of Normandy, Appendix IV, "Notes on the Organization and Equipment of the Allied Armed Forces", pp. 521-551). It was estimated that upwards of 70% of all 21st Army Group infantry casualties in Normandy up to July 1944 were caused by mortars, which were particularly troublesome because of their high rates of fire, as well as the silent approach of the bomb.

In addition to the physical damage they could cause, Nebelwerfers also had a significant psychological effect on the soldiers against whom they were used, which the Germans tried to use to their advantage. In The Guns of Normandy, George Blackburn relates an episode in which members of his Field Artillery regiment "capture" a Nebelwerfer intact and with projectiles. Deciding to put the weapon with which they have been often harassed by the enemy to their use for a change, they received a shock after firing an initial salvo. The Germans had registered the location of the abandoned mortar and waited until it was put into action, at which time they returned fire and killed a number of Canadian gunners.

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