Angle LightLED

The question occurred to me when I was at a hardware store browsing the paint aisle, noticing all of the subtle gradations and color combinations. I wondered if when a light passes through a prism and onto a white surface if every possible combination of colors comes out the other side, or if that was not the case due to how light's visible wavelengths refract in a prism, or possibly minute imperfections of the crystal prism medium (ie. at the molecular level is not a perfect medium to catch some of the subtleties the human eye could otherwise observe).

To start, I have never handled any of the Zebralights or the many lights following their model. I first saw them years back and thought it looked like a durable format for a headlamp. But nowadays, I'm seeing these standard in a lot of kits and EDC options, ranging from prepping to casual use. I'm NOT dubious of it and have armchair criticism, I'm mostly just tilting my head at it because I don't understand all the benefits. Why do you like your right-angle light, what all can it do that others can't?