I would guess that it has to do with making it easier to parse. The indents won't matter very much, but the parser sees "physical = " and knows that a property named physical is being defined. What is the value of that property? Well, there's a "{", so the value is an object. And the value of that object is everything up until the matching "}". If you have a structure more like panel 1, then it's harder for the parser to know when the value of orange.physical is complete. There might be a [orange.physical.texture] section somewhere, for example.