Openai community Design Flaw in Header

This may not neccesary be a design flaw, but why does the button on the header “documentation” leads/links to the “overview” page, maybe the word documentation means something else to the web designer and yet, in the overview page, there is another button in the header “documentation” that links to the actual “doc” page.

I just want to understand the design logic behind that lol, anyone have any ideas?