Simple: a logo needs to be able to be easily described. If you have a hard time describing what it looks like, then there is a good chance it’s too complicated.
Memorable: With an internet full of millions of logos, what can you do to make yours memorable? We are visual creatures. A concept or brand is more memorable when it’s associated with something 1) familiar and 2) natural and appropriate.

A logo that stands the test of time is the sign of a great concept and execution.
“Leave trends to the fashion industry. Trends come and go, and when you’re talking about changing a pair of jeans or buying a new dress, that’s fine, but where your brand identity is concerned, longevity is key. Don’t follow the pack. Stand out.”

Choose Something Familiar: Seeing something that is commonplace and associating it with a brand name is one of the most common techniques used in the creation of a logo. Not always consciously, mind you, but a fairly effective method for getting people to better remember a company. A couple examples highlight the point.

Timeless: A logo that stands the test of time is the sign of a great concept and execution.

Adaptable: A logo with the aim at being timeless will have to be adaptable to many different applications. It will be used online, in email signatures, on t-shirts, street signs, etc. For each of these locations, the logo may take on a slightly different look and feel, but still seem true to the original concept. The logo has to be able to endure these changes and look natural in each environment.