Datacolor User to User Support Group.

In defence of designers:

For visual thinkers the abstractions of color management are hard to
grasp. It's like I can't understand formulas. They just don't tell me
anything I can make sense of.

Look at this Delta E definition. I can stare at it forever without
having a clue.

http://www.colorspan.com/images/deform.gif

But if I look at the picture above it I get the idea.

http://www.colorspan.com/support/tools/deltae.asp