Why was the Weimar Republic unstable in the period of 1930-32?

Answer: Weimar republic was unstable because a big part population did not agree with it (a first democratic regime in German lands). They 1) were accustomed to imperialist and authoritarian government and Versailles Treaty humiliated (their perspective) ... many viewed that as unjust treatment from Allies and especially from France, 2) constitution of democratic republic (regime forced to Germany by victorious allies) was viewed as a betrayal (of so-called democratic parties, especially social democrats). So there was an extreme right whose power was growing during 1920.

Explanation: Already in 1923 there was a "Beer putch" (Munich) led by Hitler who collaborated with general Ludendorff and other sympathizers with authoritarian forms of government. Hitler was put in jail, but his popularity was growing anyway. In 1933 was legally elected as a Chancellor.