The Tiger Woods logo isn’t a golf club. The Virgin Atlantic logo isn’t an airplane. The Xerox logo isn’t a photocopier.
Computer logos don’t need to show computers, dentist logos don’t need to show teeth, and furniture store logos don’t need to show furniture.
Just because it’s relevant, doesn’t mean you can’t do better using a design that doesn’t depict the product or service your client provides.
Excerpted from Logo Design Love: A Guide to Creating Iconic Brand Identities, p.180.