In the Quiz Moderation View, the current default for the "Time" column is "Time Remaining."
For limited time quizzes, this is great.
For unlimited time quizzes, it shows the time remaining for the entire course as a countdown in months, days, hours, minutes and seconds. This display is essentially meaningless. It provides no view of how students are progressing through the quiz and you would have to be very sharp indeed to calculate from that how long each student has taken so far. I frequently use unlimited time quizzes because it seems to reduce the stress level for students who have test anxiety. This display (which I swear used to show elapsed time) is nothing but confusing. I legitimately thought it was an error when it was showing me two months or so of "Time."