> What I learned from past experiences is to never use analogies. They are almost always a source of distraction, people start to argue about the analogy itself instead of the topic at hand, which is almost always completely counter productive.

As other's have mentioned, perhaps this is only for literal minded thinkers. In Pre-suasion by Robert Cialdini metaphors are identified as the most effective persuasion device. Essentially, take something the audience understands well and use it explain something else.

An anecdote Cialdini provides is from a person who had many years of being the top life insurance salesman in the country. He used a metaphor of "when you check out, your life insurance checks in". The metaphor brought up feelings of abandonment and support in a way that people quickly understood and bought into.