With a generic logo (not creative, not tailored to a client’s needs) a company gives to the market an anonymous image of itself, devoid of any of the companies identity. Because of their overused logotypes the company is not able to establish their brand in the marketplace. In this way they’re going straight in the opposite direction than to distinguish themselves from others (which is the whole point of having a logo).

There’s a bunch of designers who submit systematically and randomly low standard logotypes, often made without reading the client’s brief. They are essentially phishing for wins.
All too frequently it happens that these designers and generic logos win contests.

Maybe the customers choose these logos because they feel familiar. What they don’t know is that the web is full of similar, clone logos. We can easily say that they’re going to be cheated.

It’s good if all the customers, who launch creative contests, know this.

These are the most overused cliches, at the moment:

This is a short collection of what you can find in some creative communities, just to give you an idea, 90% of them actually sold:

The company’s acronym cut in two colors by an arc (usually Trajan font)

The company’s acronym in “Ethnocentric” font (separated or united letters)

The company name within a two color circle

Use of the font “Satisfaction”

and others here

The company’s acronym in square boxes

Financial graphics, towers, growth lines

Roofs and cubic buildings

Following, some trends that are less generic, maybe a little more quality, but overused as much as the others:

Spheres, look at this example

Stylized cars (all similar to a standard type)

Trees where the trunks are people or hands

The evergreen swooshy men, V-men and leafy men

The rainbow circle formed by stylized humans

Shapes with swoosh lines through

Drop shapes alone or mixed with leafs and other elements

Linked bubbles or dots

Gears

And now, some examples of logos made with mixed cliches