Tarshīḥ can strengthen a figure by elaborating the borrowed source image. After “lion,” words evoking claws, roaring, or hunting can make the animal picture more vivid.
But effective rhetoric does not require maximum reinforcement in every context. An unelaborated metaphor can be more apt when the situation calls for brevity.
Whether an expression truly reinforces the source must be determined in context; some descriptions may naturally apply to the target as well.