1) Repressive state apparatus: The Nazi state had a highly developed and ruthless security apparatus, including the Gestapo (secret police), the SS (elite guard), and the SD (security service). These organizations were responsible for suppressing any form of dissent or resistance, and they used a combination of surveillance, intimidation, and violence to do so.
2) Lack of a unified opposition: The German opposition to the Nazis was divided and fragmented, with different groups having different ideologies, goals, and strategies. This made it difficult to coordinate resistance efforts and to present a united front against the regime.
3) Fear and apathy: Many Germans were afraid to speak out against the Nazis, fearing reprisals against themselves or their families. Others were simply apathetic, believing that resistance was futile or that it was best to stay out of politics altogether.
4) Propaganda and indoctrination: The Nazi regime was highly skilled in using propaganda and indoctrination to control the population. This made it difficult for people to think critically about the regime or to see alternatives to it.
5) Success of the Nazi regime: In the early years of its existence, the Nazi regime was very successful in improving the German economy and achieving military victories. This made it difficult for people to believe that the regime could be defeated or that it was worth risking their lives to resist it.
Despite these difficulties, there were still some individuals and groups who did resist the Nazi regime. These included communists, socialists, liberals, conservatives, and even some members of the military. However, their efforts were often sporadic and uncoordinated, and they were ultimately unable to overthrow the regime.