I often see "question has been closed" sometimes stating "off topic" with no other rationale. It says potential improvements should "address reasons for closure," but I'm not seeing how to view those.
This can have various causes:
The question was closed with a custom close reason one of the close voters entered as an individual comment. Look for a comment starting with a phrasing like "I’m voting to close this question because". It is unlikely but possible that the comment has been deleted, in which case there really isn't any information left to see for you.
Since you're lacking the 3k reputation for the close/reopen privilege, you only see the "public" version of the close notice. There should be a meaningful public version of each of our standard close reasons that conveys at least some information, but it's possible something's messed up there. Please link to an example so we can make sure that isn't it.