According to answer to the post What are “Community Wiki” posts?:
An answer posted to a community wiki question will also be community wiki.
What is the reason to make answer community wiki automatically in this case?
According to answer to the post What are “Community Wiki” posts?:
An answer posted to a community wiki question will also be community wiki.
What is the reason to make answer community wiki automatically in this case?
The point of community wiki is to make more editing happen, and according to this, "The intent of community wiki in answers is to help share the burden of solving a question", while "questions rarely, if ever, need community wiki" and "Community wiki is for that rare gem of a post that needs true community collaboration."
So you would only make hard-to-explain questions Community wiki so people collaborate more on the answers.