The question Python: My program is unable to perform addition correctly which asked for an explanation as to why the code was buggy was closed as off-topic; I don't know about the last two close voters, but the first three used the close reason
Code not implemented or not working as intended: Code Review is a community where programmers peer-review your working code to address issues such as security, maintainability, performance, and scalability. We require that the code be working correctly, to the best of the author's knowledge, before proceeding with a review.
The question was subsequently reopened by a diamond mod who also edited out the question as to why the code was buggy.
It's true in one sense that the code wasn't (very) buggy: it didn't follow numerical analysis best practice, but the bigger problem was in the author's understanding. It's also true that a case could be made for using the alternative close reason
Authorship of code: Since Code Review is a community where programmers improve their skills through peer review, we require that the code be posted by an author or maintainer of the code, that the code be embedded directly, and that the poster know why the code is written the way it is.
since the linked explanation includes the statement
We also expect you to understand how your code works. If you are seeking an explanation of how your code works, then we will treat the question as if someone else wrote it.
If this question is on topic, why do neither of these close reasons apply? What's the general principle which can be applied to other similar questions?