What are the reasons for the rapprochement between the Soviet Union and Germany?

What are the reasons for the rapprochement between the Soviet Union and Germany? Why was it difficult for the USSR to find mutual understanding with the Entente countries?

The USSR had an economic interest, since Germany produced modern machine tools and it was purely economically profitable to buy something there.

The second reason is the collapse of the policy of creating a collective security system.

The third is the conflict with Japan in the east, a non-aggression pact was soon concluded with it, and it was in effect until 1945.

The Entente countries in 1933-1938 pursued a policy that led to the strengthening of Germany. First, they gave the go-ahead for the Anschluss of Austria, then, following the Munich agreement, they “fed” Czechoslovakia to Hitler (Poland also took part in this, seized Cieszyn Silesia).

England and France did not trust the USSR and were not particularly eager to fight the Third Reich, which was very noticeable even in the case of Poland in early September 1939.