Why Nazism became popular in Germany by 1930?

Germany in 1930s was in a really bad state economically.

It had to pay ridiculously big war reparations for the First World War, which made their financial situation, already bad due to the world recession, really desperate. It had a big inflation problem (money earned in the morning was worthless in the evening) and people were really struggling. Nazism was promising an improvement of the economy, and in fact it did that in the first years.