Before the Battle of Verdun, the Germans were confident that their army and artillery were unbeatable. However, as the Battle of Verdun progressed, the Germans discovered that their artillery were not entirely invincible.
During this nearly half a month of fighting, the Germans first attempted to launch fierce attacks at the center of the French Army's defense line. When this attack proved fruitless, they turned their focus to attacking both flanks.
However, besides incurring heavy casualties, the Germans didn't achieve any significant results.
Especially after Bellamy adjusted his strategy, the Germans experienced unprecedented pressure in the Verdun Region. Their plan to rely on the advantages of their artillery and troop numbers failed completely.
The main reason that this kind of tactics had achieved victory on the Eastern Front was that the Russian army's equipment was too poor, and their logistics far too lacking.