Metaphors can help by tapping what learning theorists call prior knowledge to make a connection between what people already understand through experience and what they have yet to discover. We do this naturally in conversation — for instance, “The news hit her like a freight train.” By comparing the situation to something people already know or can at least imagine, we convey its intensity and urgency. But when explaining our ideas in presentations, we’re sometimes reluctant to use verbal or visual metaphors to relate to audiences. I’ve heard people say that metaphors are “off topic,” or worse, “cheap.” Though using a cheesy one can elicit groans, more often than not, metaphors offer a shortcut to understanding.
Read the full piece. Its specifically about searching for the right metaphor in a presentation but so long as you don’t lurch into cliché, it’s surely going to be valid until the cows come home.