Although the Enigma machine at first seemed nearly impossible to decode, eventually the Allies successfully were able to get breakthroughs in the machine and finally solve the Enigma machine.
A major reason for the eventual success was although the Germans used different key words each day to further stifle the Allies, the Germans sent a huge amount of these messages which gave thousands of words the ability to be analyzed. Because of the vast amount of messages sent, it gave the Allies a great number of chances to solve the Enigma machine. Perhaps if the Germans had taken a step further and alternated using the Enigma machine with a different type of encoding device, it would have given the Allies almost no chance at deciphering their messages. However, the change of key words was a brilliant idea to make the Enigma machine more difficult to solve.
Another reason for the Allies solving the Enigma machine was as a result of the Germans sending messages concerning positions of their U-boats and where others needed to be. The Allies knew where the U-boats were when attacking their boats because the Allies boats were able to be tracked. As a result, when the Germans were communicating where to go, the Allies knew what the code represented which helped them figure out the key to the Enigma machine. Had the Germans used a wider variety of codes, not sent the great number of messages encoded by the Enigma machine, and not committed this fatal flaw, the Allies possibly could have never been able to solve the machine during World War II which could have greatly affected the final outcome of the war.