Out of class evaluations doesn't mean electronic. It could be problem sets, essays, longer-form things like projects. All of these things are difficult to do in a limited time window.

These limited time-window assessments are also (a) artificial (don't always reflect how the person might use their knowledge later) (b) stressful (some people work better/worse with a clock ticking) and (c) subject to more variability due to the time pressure (what if you're a bit sick, or have had a bad day or are just tired during the time window?).