Great Question... Many students may feel pressure to answer questions according to what they see as more "socially appropriate" responses if they feel that teachers will see their answers. They may also feel pressure to engage in "impression management"--answering in a way that creates a more ideal impression of themselves if they believe the teacher has access to their answers.
Teachers can see an overall score range that gives them the feedback they need to support students without infringing on the student privacy required for greater candor in responses.
In Short, we don't make the responses available to ensure student privacy and to encourage honesty and accuracy in responses.