How can the terrazzo floor get brighter and brighter?

You confuse the processing of terrazzo floor to a certain smoothness with the daily cleaning of the residual dirt in the cracks.

Terrazzo floor, etc. It used to be rough, and it was repeatedly polished with grindstones with different finishes, and gradually reached a higher finish. But to a certain extent, it is enough, and the cost of re-polishing will increase greatly; Also, the dust brought by people walking around every day is only a small friction under the microscope. When these things are scratched on the smooth terrazzo floor, the original smoothness of the floor is destroyed, and soon it will become rough. So terrazzo floor is not and does not need to be as high as a mirror.

The example you gave is that the ground is very muddy in rainy days, and the ground is not so dirty and there is nothing in it. Compared with dry soil, sawdust is softer and can protect the ground, which is different from brightening the ground.

If you have time, you can clean up this hard ground, and then polish the ground with very fine grindstones that polish the terrazzo floor, so that the ground will always be as bright as a mirror. But then again, once polished, you will know its effect and necessity.

By the way, no matter how polished materials like terrazzo are, they can't reach the high finish that glass and metal can achieve!