Jekyll and Hyde

There's something weird about the way I go about drawing. For example, take my latest somewhat "decent" drawing "Midnight Flyer". I just sat down, sketched out the form and layer upon layer, things just went right. But then there are times when I actually feel inspired to draw, with something specific in mind, and no matter how hard I try or how many revisions I make, I just can't get it to look the way I want! It's frustrating, and like any art form, the more I practice the easier it will get. I just find it strange how I can feel like two totally different artists at times. YA KNOW? I think it's a case of intermittent stupid hand syndrome.