Its “war guilt” article humiliated Germany by forcing it to accept all blame for the war, and it imposed disastrously costly war reparations that destroyed both the post-World War I German economy and the democratic Weimar Republic. The treaty, therefore, ensured the rise of Adolf Hitler and the Nazi party.
treaty forced Germany to surrender colonies in Africa, Asia and the Pacific; cede territory to other nations like France and Poland; reduce the size of its military; pay war reparations to the Allied countries; and accept guilt for the war.
The reason they adopted this was to "A.Justify Revolution". This was because up to this moment there really had not been a formal explanation of the goals of the movement.