Here is one of my rough story sketches-very scribbly but it shows the character's pose and his emotion. The trick is to take the scribble and turn it into a finished layout or animation pose that is constructed but still retains the guts of the sketch.
Sometimes artists don't use enough space in their poses. In the drawing above, the shapes are all cramped and too close to each other. The eyes are too close to the edge of the head, the space inside the bow tie is almost non-existent. The shapes are overall - too skinny. This makes the drawing hard to read because all the areas of space are too small, so the lines are all too close together.
Sometimes after I analyze the story sketch and then carefully try to construct it for a layout pose I lose bit of the emotion. I might then just redraw it from scratch to make the pose and expression stronger - once I have analyzed how it works.