I have created the golden metaphor to explain SEO to clients. I was trying to explain SEO to a non-technical 80 year old client (the single best businessperson I have ever met) and I came up with the following metaphor.
Start to explain seo to clients like this:
Your website is like an ambitious young man trying to meet lots of attractive women. Web users are like impressionable women who make a lot of bad choices with men. Google is like her parents. Using a search engine is similar to letting the woman’s parents pick suitors for her at a high society party.