One of the reasons of the failure is because it had failed to prevent the Second World War to occur. The purpose of the treaty itself was to stop another big war to exist again on this earth, yet it had unsuccessfully done so. The war still happened and the destruction of it was even larger and more serious than in WWI and other war in history of humankind due to the fact that the technology is increasing, and thus the weapons using are more powerful than ever, for instance, aircrafts, tanks, machine guns, and especially the use of nuclear bombs in Japan to end the war. Consequently, it resulted in dead of 75 million people including 20 million soldiers and 40 million civilians.
Furthermore, the cause of failure of the treaty was because it was lack of the enforcement mechanism and lack of willingness of the allied powers. Many terms stipulated in the treaty were not implemented. For example, the 14 points of President Woodrow Wilson including “1) no more secret treaties, 2) countries must seek to reduce their weapons and their armed forces, 3) national self-determination should allow people of the same nationality to govern themselves and one nationality should not have the power to govern another , 4) all countries should belong to the League of Nations,” and an intention of France in dividing Germany into smaller states did not occur, and thus it just caused the treaty to become weak; as a result, Germany could take the advantages of it.
The monarch couldn't raise taxes without the parliament's consent
The situation prevailing in a market in which buyers and sellers are so numerous and well informed that all elements of monopoly are absent and the market price of a commodity is beyond the control of individual buyers and sellers.