The physics of the color gap
Computer screens emit light — they start from black (no light) and add red, green, and blue channels to build color. Print inks absorb light — they start from white paper (all light) and subtract wavelengths using cyan, magenta, yellow, and black pigments. The gamut of printable colors (the CMYK space) is smaller than the gamut of displayable RGB colors. Highly saturated blues, greens, and certain purples exist in RGB space but have no equivalent CMYK mixture that produces the same visual result. When these colors are sent to a printer, the RIP (Raster Image Processor) converts them to the nearest printable equivalent — which often looks noticeably duller on paper than it did on screen.
