Excerpt from the NPR Ethics Handbook:

"News outlets are 'driven by deadlines, and under time pressure, you are sure to make mistakes — about names, affiliations, places, and so on. These errors are regrettable, and you should always correct them. … But they are not nearly as serious as failing to be fair and unbiased. That may not only discourage people from listening; it can undermine your station’s or network’s reputation — one of its greatest assets. Even occasional lapses have serious consequences. The price of good journalism is eternal vigilance.' "
Jonathan Kern in Sound Reporting. [Excerpt from the NPR Ethics Handbook, http://ethics.npr.org/]