Sam Hey:

Here’s the deal – imagine you have an iPhone 4 and the person who called you has an iPhone 4 (I know for a lot of you nerds this is a real stretch), and you take the call, and the FaceTime tone dings indicating that your caller wants to do FaceTime, and you’re on your couch ensconced in a wifi signal and you could do FaceTime — but you don’t want to. What do you do? “No thanks, buddy.” No matter what perfectly valid excuse you give, the inevitable interpretation on the other end of the line is “I don’t really want to see your face right now.”