Logos are the face of a company, the identity, the concise interpretation of who you are and what you're about. A logo should speak to the product or service you offer as well as to the type of company you are. Be it fun, whimsical, carefree, or solid and stately, a company's logo is the lasting mark that will inform clients and make a company instantly identifiable.
I design logos after consulting with the client and getting a good understanding and feel for who they are and what their company does. Logos should never be simply slapping pre-made icons together and reselling them. Care should be taken to ensure the logo adequately conveys the client's message and identity.