What factors contributed to the statement on the western front

The "Race to the Sea" which occurred during 1915 along the Western Front led to both sides being fully entrenched and stalemated until 1917.  Part of the reason the stalemate occurred in the West and not the East was (as it was again in World War II) because France was not the objective -- Russia was. The von Schlieffen plan failed precisely because Germany wished to insure its success - by committing most of its troops to the East, it could hope to defeat Russia.  By fully committing troops early in the war in the West as the plan called for, overrunning France, and redeploying them to the East, Germany could have prevailed against both countries. But the German High Command feared that committing troops Westward would slow down the main thrust to Russia.  By scaling back, the offensive into France failed, and the Front became defensive on both sides until later in the war. Rather than countering the French trench by trench throughout 1915, the Germans could have fully invaded and won.  Poor generalship in general, and poor appreciation of current weaponry specifically was characteristic on both sides during the whole war.

the name of the theory is landmass theory.