Hi K4llegro, good job on finishing the box challenge! I imagine you will be quite relieved. I will try to handle your critique, trying to point out where you did well in my opinion and where there could be room for improvement.

Starting with a general consideration, the broad trajectory of your work tends towards improvement over time, with the occasional misstep here and there as it is normal with a repetitive task. Your boxes start as confident but somewhat wonky at the beginning of the challenge, often resulting in these early boxes having sets of sides that converge in pairs rather than near a single point, as if we were looking at an irregularly shaped box in isometric view rather than a rectangular box in 3 point perspective. However as the challenge goes on your accuracy improves and you manage to produce more consistent convergence of your boxes with a fair accuracy.

More on convergence, you experimented with a fair variety of shapes and inclinations. You seemed to struggle a bit with boxes with more pronounced foreshortening in the beginning, but with the general quality of your boxes improving further down the challenge your ability to capture foreshortening followed suit. In a couple of boxes you have placed your extension lines in the wrong direction, but seeing that otherwise they are placed correctly it seems likely to me that these were instances of momentary distraction rather than misunderstandings of perspective.

As far as your line work is concerned, it looks smooth and confident for all the structural and lineweight lines all throughout the challenge. The hatching lines look sometimes a bit uneven and wobbly however. While for the purposes of the exercise hatching lines are a minor concern, remember that in this course lines should always be traced with confidence using the ghosting method, and hatching is no exception.

At last, some comments on the back corner. The back corner of the box is usually the part of the challenge students struggle the most with. It is not unusual (and it happens often in your boxes) that one or multiple of the hidden sides converge less precisely compared to the remaining 3 sides in the same direction. This is due to the fact that if we start beginning drawing the box from the front, the back corners will be both difficult to pinpoint because we have to ghost in 3 directions that must be consistent with the previously established vanishing points and because all the little convergence mistakes we previously made will pile up at that point. There are multiple possible ways to improve this detail. A possibility is trying to start to draw from the back corner instead and build up the rest from there. Another method I tried is to choose 2 of the 3 directions that form the back corner, ghost in the first direction, place a small reference mark where you think the corner will be (thus fixing one of the segments) and the ghost in the second direction to find out where the 2 lines actually intersect.

As a whole, I think you did a nice job in this challenge and demonstrated that you could improve from your previous mistakes. Keeping in mind the things you could improve, I'd say you can move on to lesson 2. Good luck and stay motivated!