Why did the western powers follow a policy of appeasement even though it seemed to encourage more aggression

The Western powers were most likely following a policy of appeasement in hopes that this would prevent another World War. The Munich agreement, in which Germany is able to expand their power and territory, was meant to satisfy the Germans appetite for land that was taken away from them after World War I. This agreement was supposed to end the conflict of German expansion. However, this was just the beginning. After seeing that the land given to him in the Munich Agreement was not enough, the Western powers had no other choice but to declare war on Germany.