Working on bikes may not be rocket science but it isn’t completely uncomplicated either. There are lots of little details that can go wrong which can make the bike unridable. I often use that as a threat (jokingly). Don’t mess with a man who can turn your pee green or can make your bike unridable in 30 seconds

That said, I don’t usually mess with brakes. I can rebuild them but there really is no reason. They aren’t worth the effort. If the brakes aren’t working, they are generally cheap enough to just replace. That also assumes that the brakes aren’t working which doesn’t happen all that often. I certainly wouldn’t take them apart just for fun. Pick something else to work on.