لأن معنى المجاز هو اللازم فقط
For the meaning intended in majāz is the connected meaning alone.
“Only the concomitant” means that the transferred intended sense is what the speaker communicates in this figurative use. The original literal sense is not intended there because the excluding clue prevents it.
If “Zayd is a lion” is used to praise his courage, it does not assert that Zayd is literally a wild animal. It attributes courage to him through the figurative image. None of this abolishes the established dictionary meaning of the word “lion.”