Before evaluating the excellence of a metaphor, identify its working elements.
1. Determine the subject and comparison image, or the two complete situations.
2. Identify a resemblance fitting both sides and the communicative purpose.
3. Check that the audience can grasp the link directly or through a shared or specialist convention.
4. If the direct metaphorical claim is intended, make sure the wording has not collapsed back into overt simile.
5. See whether imaginative details strengthen the basic image rather than replace it.
These tests distinguish technical classification from expressive success, making evaluation reasoned rather than impressionistic.