Why is Concrete Milling done

Irregular concrete surface is unsafe for wheel tires. Due to this irregularity the noise caused due to friction increases too. Milling helps in restoring the smooth concrete surface. This results in better road experience.
It is a great way to increase the aesthetic appeal of concrete surface. Milling polishes the upper surface and makes it shine.
Milling increases the durability and life of the roads.
It is an environmental friendly way to recycle the paved areas. The new top layer of concrete uses scrapped off pieces of old layer as aggregates. This means it is ecologically safe.