What is the rationale for some authors of books on 'illahs, which are for hidden 'illahs, including some hadiths that have apparent 'illahs such as disconnection and others, despite their rarity?

The questioner : I mean, with the mention of this statement regarding the specialized books on specific hadiths, the books that are on 'illahs, they mentioned that the books that specialized in 'illahs, such as al-Daraqutni's 'Illal and others, are only for hadiths that have hidden 'illahs, and the scholar wanted to clarify the 'illah of this hadith, meaning that without it, the hadith would appear valid on its surface. Sometimes we find in these specialized books on hadiths with 'illahs, hadiths whose 'illah is apparent, such as disconnection, or obscurity, or the weakness of the narrator, or such. So what is this attributed to, even though this is rare and not much in such books? But what is the rationale for including such a practice or such a type of apparent 'illahs in books specialized in hidden 'illahs?

The Shaykh : Can I understand that this question is disconnected from what came before it?

The questioner : You mentioned to me regarding the specialization of books, you reminded me of your answer that books have specialization, but no, this has no connection, yes.

The Shaykh : Okay, may Allah reward you, since you mentioned that this is a rare matter, that the 'illah is apparent, yet they mention it in books on 'illahs whose subject is uncovering hidden 'illahs.

The questioner : Yes.

The Shaykh : There is nothing strange about this, may Allah reward you, because as you are, incidentally, a question after that question.

The questioner : It is a question other than this question, so they included the hadith in a chapter other than its proper one, what Allah wills.