Flawlessness certainly isn't what we're looking for here - but I am thrilled to hear about how your discipline has developed. Like everything else, patience is one of those skills we work on and nurture, rather than something we're simply born with.

Starting with your cylinders around arbitrary minor axes, I'm pleased to see the fastidiousness with which you've checked the alignment of your ellipses, and I'm also pleased to see that you covered a fairly wide range of rates of foreshortening.

There were maybe a couple (29, 83, etc.) where you neglected to include any scale shift at all, which left them looking a bit odd. Remember that the vanishing point of those side edges would only ever go to infinity, resulting in them being parallel on the page, when the cylinder itself is oriented to be perpendicular to the viewer's angle of sight - something that would be so rare that we may as well assume that it's never going to happen while rotating our cylinders randomly as we do here.

Still, these were just odd blips on the radar. The vast majority of yours show a proper grasp of how the various manifestations of foreshortening (the scale shift where the closer end is larger and the farther end is smaller, the degree shift where the closer end is narrower and the farther end is wider) all work in tandem with one another, so I didn't really catch any where there was a more dramatic shift in one, but no shift in the other. So nice work!

Continuing onto your cylinders in boxes, here you really knocked it out of the park. All your line extensions are fantastic, and your convergences are far more consistent than I'm generally used to seeing. Most importantly, I can see your ability to estimate the construction of boxes that feature a pair of opposite planes which are proportionally square improving a great deal throughout. Basically by checking whether the ellipses' line extensions (minor axis and contact point lines) converge towards the box's own vanishing points, we can determine whether those ellipses represent circles in 3D space. If they do, then we can also assume that the planes enclosing them must be squares in 3D space.

And of course, as we check those convergences and find where they can be adjusted to bring them more in line, we inadvertently train our brain to focus more on building boxes that match this criteria. Given that we're going to be getting into all kinds of geometric constructions in the next lesson, this will definitely help you as you figure out how to build boxes that suit the objects you're constructing.

So! All in all, really great work. I can definitely see what you mean by developing discipline after looking at those cylinders in boxes. I'll go ahead and mark this challenge as complete.