Me: Hello! Attached you will find two concepts for the book design. Please let us know which one you prefer and then we will design the rest of the pages.

Client: We prefer Concept B but we aren’t sure we like the color. Can you please make it blue?

I looked at Concept B.

It was blue.

Me:  I’m happy to change the color, but the concept is already designed with blue as the predominant color. Are you looking at the file on your screen or printed out? Sometimes standard office printers can make colors look off.

Client: I’m looking at it on my screen and it is definitely gray and not at all blue.

Me: Hmm… that’s strange. Take a look at this file and let me know what you think.

Clients: That’s great! Thanks. You can go ahead with the rest of the design.

I changed the color by shifting the color code a single digit. To the untrained eye, both files would appear to be the exact same blue. I still have no idea what happened there.

Source: Clients from Hell