Companies get added to and subtracted from the S&P 500 (^GSPC 0.13%) every year, but that doesn't make it any easier for shareholders in the companies that get the boot. In the following video, Motley Fool contributor John Maxfield discusses why this happens, paying special attention to recent exiles J.C. Penney (JCPN.Q) and Abercrombie & Fitch (ANF -0.74%).