If you are upgrading to SharePoint 2013 and use Site Columns, you need to go check the settings post the upgrade.

In SharePoint 2010 you can use renamed site columns all over any of the subsites in the site collection no problem.  After the upgrade to 2013, all the custom site column names are stripped out and defaulted back to the original site column name.  It’s a pain in the butt because now you have to go back to every list and library and change the name back again.  Not only that, but even after you’ve renamed it, it continues to go back to the original name!!  Incredibly frustrating.

Hope you had those great descriptions in every list or library so you know where your site columns were used…