[rothron]

This topic has been written about in more depth by people who didn't try to work it out by themselves.

The classical artists color wheel is based on pigments. Printers use dyes. Screens use light. That's the whole reason why the primaries are different. The wheels are just tools.

[beardyw]

Blue and Yellow Don't Make Green by Michael Wilcox covers the mechanisms behind subtractive colours (paints) pretty well. Also explains why it will never make a really bright green.