because...
Winston Churchill
The outbreak of another world war in 1939 was in part caused by the British appeasement-policy of the 1930s. Other factors were responsible, as well, such as the intentional and determined aggression of Germany.
Britain exercised a policy of appeasement with Hitler because initially, his demands were reasonable. The belief was that if appeasement was used, he would eventually become satisfied and stop his aggression. The British Prime Minister, Neville Chamberlain believed that appeasement was the appropriate tactic.
Appeasement Policy
The British remembered how terrible WW I was, and they desperately wanted to avoid another such terrible war. They believed, incorrectly, that if they made concessions to Hitler he would be satisfied and would not attack them.
nothing
Appeasement was a foreign policy strategy that the British thought of, and was agreed upon by both Britain and France. Appeasement did not work, since Hitler ended up trying to annex Poland, which lead to a declaration of war.
because it just was
"appeasement"
appeasement
Prior to World War II, Britain tried a strategy of appeasement with Hitler. It didn't work, and Hitler ended up taking Austria and Czechoslovakia.
Appeasement will forever be associated with British Conservative Prime Minister Neville Chamberlain. In signing the Munich aggreement he appeals to Hitlers 'better nature'. Put simply Hitler didn't have a better nature. Appeasement is a vain attempt to avoid a repitition of WW1 in Europe.