If you’re interested in reading more about why Discourse works the way it does (and it’s largely because the designers have quite strong opinions about what’s wrong with most forum software), I’d really recommend visiting their site at discourse.org
In particular, their own discussion forum is very interesting and enlightening, plus you can ask questions of the devs (who are very active there) and make suggestions.
Discourse is very different from forum software I’ve been used to since the dawn of the category. (I’m old, I promise you.) I really like this new approach.