Why was important to take Czechoslovakia before WW2

Documentary cut of world war II movie. On the 29th of September 1938, the four European leaders:Benito Mussolini, Adolf Hitler, Neville Chamberlain and Edouard Daladier met in Hitler's Munich. The Czechoslovak President Benes was not invited and neither was the Soviet leader Stalin. As a matter of fact Benes was allowed to come to the meeting but merely as an observer and he was not allowed to actively participate. One could say that Hitler only wanted him there if they had some practical questions about the actual splitting of his country. Benes received the papers after the negotiation, but only to sign them. The Czechoslovak people still refer to this meeting as the meeting that decided their future WITHOUT THEM.