What's the Point of Error Codes?

I understand that in the 1980s when 'puters were comparatively primitive they couldn't spare the memory or storage space that detailed messages would require. I'm more wondering about modern times. I was having an issue getting my Wii online, and was given error code 209600. Going to Nintendo's online support I wasn't given anything specific, just a few paragraphs of vague nonsense. Why do I need to go to Ninteodo.com for this? The Wii has more than enough storage space to include the entire works of Shakespeare, so why do they need to use an error code, rather than just popping the exact same info on the Wii?
Please, for the love of God, don't respond with "IDK blah blahblah." If you don't have an idea don't feel like you need to tell the world how stupid you are.

If errors were written out in full, you would likely have a text so large and confusing as to be as useless as the error codes would be without explanations. The error codes are meant for technicians to narrow down where a problem is. Error codes don't always give a precise indication of the problem generating the error so if replaced by text, the explanation wouldn't get you any closer to a solution and would for most people just add to the confusion and frustration caused by the problem.