Some poeple don't like contractions, saying they are "unprofessional". I work at a nonprofit that has members that serve a specific scientific discipline, and if we use a contraction anywhere on our website, we get e-mails and phone calls. I slam my head into the keyboard every time I hear it, but I go ahead and remove it all.

I find this quite odd, as in all of my college-level writing courses, we were encouraged to use contractions. Most of my company's members tend to be relatively old, so this could be a more recent movement in the language.