heavy equipment operators have little difficulty

My comment is meant to be entirely constructive, a gentle suggestion without any hint of criticism. When I watch these interesting videos I often wonder about the end-use. Is the 'sand' too coarse for use in mortar for bricklaying? Is it really aggregate for concrete? What about the medium sized rocks that fall off the sieves? Are they for road building or something else? I watch these interesting videos and often wonder where the material is going and what it is used for. I wonder whether other people would be encouraged to watch if we knew a little more about the whole industry, which appears to be a very constructive use of resources.