The most challenging part of factorio is routing inputs and outputs in 2D. If you build naively, intersections between ingredient belts choke the life out of yo

The most challenging part of factorio is routing inputs and outputs in 2D. If you build naively, intersections between ingredient belts choke the life out of your factory (3 utilities problem). Bus guarantees building space with easy access to all ingredients. Sure, if you already know what you're doing, you can plan ahead and leave space for the right things. For everyone else, it simplifies the game to a manageable level.