It sends you to the play page.
The play page itself may deserve a few more criticism though, chief among them being the graph on the right side which takes up half the screen and, in my view at least, serves almost no purpose apart from looking weird and complicated.
It seems Hanayeol also proposed that this “find game” page be merged with the landing page, which I think is a great idea. I don’t really get the purpose of the current landing page.
Another regular complaint about OGS’s UI is the search field which is hidden in a menu instead of being displayed in the upper right corner as is common in webdesign.