Space.
You know when you sit down and think "Okay, I am going to try drawing this, I am going to try my hardest, take no short cuts and see how it turns out." Then you spend your entire day on the drawing and when it's done you really want to be proud but you've been staring at it ALL DAY so you are just sick of it. Yeah, that's what these two drawings are a result of. Man, I'm in a slump. I'm not a the point where I need to drop all map parts and take a break but it's getting there.