Why didn't the communists win the upper hand in germany after the economic crash?

As the crisis of capitalism deepened and Hitler's Nazis were rising, the Communist Party adopted the "Third Period" line, attacking socialists with accusations of fascism and creating a deep division in the left forces. Neither party remained strong enough to oppose the rising of Hitler.

to answer this question you need to explain more

an economic reason that the south needed a reconstruction plan is that plantations, factories, and other businesses were destroyed during the war.