Tell why winston is not killed each time he is tortured

It would have been to easy.

Explanation:

It would have been too easy to kill Winston Smith, just as it would be too easy to kill any opponents to its regime. However, the problem is that this would not actually gain them any support. What the Party has to do is to do the unthinkable: to make those who oppose it come to love it and everything it stands for. It is for this reason therefore that O'Brienand the Party take such time with people such as Winston Smith and Julia

In 1984, we learn that when Winston shows that he does not agree with the ideals of the Party, he is captured and tortured. However, he is not killed. The main reason for this was the fact that killing Winston would imply that the Party does not have the absolute power that it claims to have. Killing Winston would be equivalent to admitting that some people can have different views, and it might lead to him becoming a martyr. Instead, the Party uses torture in order to show that no one can escape its power and exercise free thought.