Apple's big foray into advertising isn't working out as expected. Six years after launching iAd, the company will soon take a step back from selling ads on its own platform, and will instead open things up directly to publishers, BuzzFeed reports. Consequently, Apple will also phase out its iAd sales force. "It's just not something we're very good at," one source told the site. The move is a bit surprising -- iAd was once heralded as a potential revolution in advertising (Nielsen once called it more effective than TV commercials) -- but it's also a sign that Apple is finally refocusing on its own strengths.