The universe/galaxy/solar system isn't designed by a committee.. There isn't some "importance" these features were introduced to achieve. They are where they are because the physics work that way. Lot of dust floating around, collects and becomes rocks which develop large gravity wells due to their collective mass. That gravity in turn pulls more towards it, or away from it as other gravity wells make their presence felt. Over billions and billions of years things start to form and develop a pattern once the initial chaos thins the herd of start dust everywhere. Orbits fight gravity, moons are a thing. Maybe two moons hit each other and shatter, which over eons forms rings which over more eons will fall into the planet they orbit.... there's no "design" importance to any of these things. But, other things can be side effects of them. It's not the other way around though.