"Solved" bug or intentional?

I believe you are still misunderstanding the point of my topic.
I’m not questioning the use of:

image

I understand that having a bigger, more obvious button is good to encourage users to mark as a solution. My question is: why isn’t it the same for both cases to create consistency? I don’t see the reason behind using a full version in one case and just an icon in the other. I think it should always be the full version.