When the internet was new, I had a boss who insisted that I make our organization’s website use the same green that she saw when she printed a webpage. She correctly pointed out that the green on her monitor was different from the green on her printer. No matter what I did, this was true. I briefly tried explaining the difference between emitted light and reflected light, but it didn't take.
This was after the gig where a retailer had the brilliant idea of scanning color swatches and mailing the images to manufacturers on another continent to match. Now to me and to a lot of guys one pale yellow looks pretty much like another, but to merchandisers there is a huge huge difference – even I knew the project was doomed to failure.
The genius who had thought of the idea was a grandson of the founder – his hair was perfect! – so I soon shut up and took the paycheck.
The project was officially a success because the organization had learnings.