First and foremost, prisoners were physically weak and too frightened. They were unable to withstand because they understood how small their chances were against the soldiers.
First of all, prisoners could not make large-scale efforts to resist since they did not get enough nutrition to be strong. People were too sick, weak, and cold, and all their thoughts were about food. They were starving, and it was physically impossible for them to confront the guns.
They just could not fight back since they were afraid and felt hopeless. Sometimes hope leaves even the most persistent ones. Those who for a long time miraculously resisted diseases and dangers finally lost faith in life. Their bodies and mind surrendered, and they could not pray for anything or combat the enemy anymore. Even those who were physically able to resist realized that their chances to survive were too small. The Jews initially were calm, religious, and peaceful people who could not fight since it was out of their character. They were simple people, business owners, traders, not soldiers, so they did not feel they were capable of large-scale resistance.
Perhaps, another reason why the Jews did not counter the Nazi soldiers was that they were a bit divided and lacked unity. There were no strong leaders among them who would initiate the resistance. Many of them thought that confrontation would only lead to even more massive deaths. They understood that their chances were negligible in comparison with their enemy.