A logo is a flag, a signature, an escutcheon, a street sign. A logo does not sell (directly), it identifies.
The logo is the first touchpoint of the brand, and the visual anchor of the company's brand identity.
Simplicity is not the goal. It is the by-product of a good idea and modest expectations.
A good logo is distinctive, appropriate, practical, graphic, and simple in form and it conveys the owner's intended message.
Every advertisement should be thought of as a contribution to the complex symbol which is the brand image.
Logos and branding are so important. In a big part of the world, people cannot read French or English, but are great in remembering signs.
A logo derives meaning from the quality of the thing it symbolizes, not the other way around.