When you take a color blind test and you do not have the condition, you think, what idiot cannot see the colors in this test.
But for someone who is color blind it's difficult.
If your mother's brother is color blind and you are a boy, then you will be color blind. Guaranteed. Always a boy. Always passed by the mother. There may be one or two girls in the world who are color blind. That's out of 8 billion people.
My Dad and uncle (of course) were color blind, my brother and I are not. For my Dad primary colors were easier than a mix.