What are the risks of recommending a friend for your workplace?

Question: “I’m about to put a friend of mine forward as a job candidate with my firm, but despite my confidence in her, I wonder if the downside of recommending someone I know is too great. Sometimes people don’t work out, and this could reflect on me. Am I being selfish, or am I justified in hesitating to commit myself to her cause?” – Jen, Email Marketing Representative