Does time pass quickly or slowly?

Chapter 12: The Events of the Summer
“For living men, the units of time always have a value, which increases in ratio to the strength of the internal resources of the person living through them;… the future stood in front of us, grey and inarticulate, like an invincible barrier. For us, history had stopped.”

This passage made me ponder, first of all, about what it meant, and also about when I feel like Levi felt in this paragraph. First, I think the passage means that time was of no value to the prisoners of the camp; it didn’t matter if time passes quickly or slowly, since all expected to die in the camps. The passage of time only neared their doom, yet they did not regret it. Although it is commonly believed that one should not accept death so easily, trying to survive as much as possible, I guess the conditions in the camp destroyed the prisoners’ will to live at all. Considering this, the attitude in the passage was, in a sense, “right” to have.
I also thought that the passage could mean that when one is in a formidable or undesirable situation, time passes slowly. When I put myself in Levi’s situation, time would definitely pass sluggishly when I work all day long in the cold winter weather without adequate clothing on. Moreover, I also feel this in my everyday life. When I am in class, I often become bored and feel that time does not pass at all, whereas the times I spend with my peers seem to fly by.
Sometimes I wonder why God would make things undesirable like this; “why can’t time pass slowly when I am having fun?” I do not understand, but I know God has a reason for everything, and this is the best way things could be done.