Signatures should be brief and short has possible. Your name and e-mail to contact you properly because you use a fake (ghost) e-mail address in the reply area is a good signature. Others like to use Phrases and Famous quotes, while others like to have their webpage address on the bottom.  It's however bad to use all of them, especially if your quote is like two or more lengthy sentence long. Think in this way, if you post up a two-sentence response and your signatures is more than the response, you need to trim something or a lot of it.