Silhouette is a speed test for clarity
If the pose collapses into a single dark blob, the viewer has to work too hard. Clear silhouette lets the body read quickly before interior detail even matters.
This is especially important for combat poses because motion needs to be understood in an instant.
Look for separations and directional asymmetry
Good silhouettes often depend on one limb breaking away from the torso, one side compressing while the other extends, or a weapon line countering the body angle.
Those contrasts help the figure feel staged and deliberate rather than symmetrical and static.
Practice by reducing reference to flat shape
One useful drill is to simplify a pose into black shape only, then rebuild the figure from that read. This reveals whether your understanding depends too much on interior contour.
Once silhouette is strong, you can layer anatomy and costume with much more confidence.