I've had a lot of trouble entering the Windows serial numbers when installing Windows. The B and 8 look alike, ditto for O and 0. I've had to use a magnifying glass on it.
Apple's online documentation pages have also tended to be light grey fonts on white. My eyes would ache trying to read them. I find their choices baffling. It's like they were so focused on design they forgot about people simply wanting to read it.