Often the question about Munich is that Chamberlain bought time for British rearmament by his appeasement at Munich. What this ignores is that contemporary evidence does not indicate in the slightest that Chamberlain appeased Hitler to buy time.
Instead it indicates that Chamberlain really thought that he, through appeasement, was making a lasting peace. Further Chamberlain continued right until the German invasion of Poland to think in terms of appeasement of some kind. In fact between the state of Hitler's invasion of Poland on September 1, 1939 and the British declaration of War, Sept 3, 1939, Chamberlain sought to find a reason not to go to war with Germany. Chamberlain's Cabinet revolted and basically forced him to declare war.
Further the British rearmament program was put in place before Chamberlain became Prime Minister and Chamberlain was forced to allow it to continue, despite his misgivings about it. Also Chamberlain was responsible for ending the Ports arrangement with the Republic of Ireland, which during the war greatly impeded the British fight against the U-Boat menace.
Also this fixation on Britain ignores that Germany was also unprepared for war. In fact Germany was so unprepared that several German generals were planning a military coup against Hitler if a war started. They actually endeavoured to contact the British government but were rebuffed.
In fact Germany was so unprepared that Hitler's generals basically forced Hitler to accept Chamberlain's mediation. The Generals felt that Germany was woefully unprepared for war and looked askew at the threadbare forces they would have to leave in the west while they dealt with Czechoslovakia.
For we now know that Hitler really wanted a war with Czechoslovakia, which was why Hitler before Munich kept upping the stakes, to basically force a war. In fact right to his dying day Hitler felt he had made a big mistake in giving in to his Generals and not having his war in 1938.
As for benefits. Yes appeasement gave Britain and France more time to rearm, (Although as stated above this was not Chamberlain's goal.), but it had huge costs which, in my opinion, outweighed the gains.
First it gave Germany more time to arm. Secondly it gave the resources of the Czechoslovakian state to Germany. This included much Military material, the significant industrial resources of said state along with a significant armaments industry. It also gave the financial and fiscal resources of said state to Germany. (This included significant resources of foreign currency, which Germany was short of, and gold reserves. In one of the last gestures of appeasement Chamberlain allowed the part of the gold reserves held in Britain by the Czechoslovakian state to be given to Germany after Hitler liquidated the Czech state in March of 1939 and turn Slovakia into a protectorate.)
Further Munich basically destroyed the western system of alliances in Eastern Europe opening up the area for German, political and economic domination.
So the bottom line is that in my opinion Hitler's Germany benefited more from Appeasement at Munich than did Britain and France.
The irony of all this is that Hitler saw his greatest diplomatic victory has a failure and mistake.
