Sometimes it's the small things: While I felt good about the proportions in the sketch phase and first coloring stages, I realised that Kageyama didn't feel quite right and adjusted his head, hand and front foot. Usually I try my best to catch those errors early on but sometimes only time and rendering actually unveil those mistakes when they become more and more apparent.
As in the second example the chin was too prominent. Sometimes it's down to preference but within the margin where things work and don't work it helps to "over-adjust" until it becomes clear if it's too high or too low and then settle for something inbetween.
Especially as the artist myself I sometimes tend to get "blind" for my own art because I'm looking at it for too long - then it's always appreciated when customers have a keen eye and don't hesitate to correct me if it becomes apparent, that I'm missing things. Even after a lot of practice, some angles and gestures still challenge me, so it's a continuous progress of learning and improving!
The first drawing is still a WIP of an ongoing commission, so be excited for the final product - hopefully without any further adjustments!