The #250BoxChallenge at #DrawABox continues to be frustrating.
My working theory is that the visible sides need to be perfect, or at least nearly so, otherwise the hidden vertex at the back of the box cannot be correct, and thus the edges that connect to it will be off. This seems to bear out in practice, as a box drawn with visual vanishing points off the page results in a more or less correct rear edges.
The problem I have is whether this is an issue of skill in drawing lines and "ghosting" where the line leading to the vanishing point should go, or a conceptual one, where I am not imagining the VP and the line to it well enough. At this point I don't know.
I'm probably beating myself up over this too much, given I'm only at 60/250 boxes, and the remaining 190 attempts will provide practice for both. But I expect I will continue to worry as I go along for the next few weeks.