Sometimes you're just interviewing someone and you're thinking the entire time, How can I get through this really quickly? Because I know this isn't gonna make it. This person is either too long-winded or deathly boring, or they don't have the point of view that supports what you're trying to do in the piece. Or often people misrepresent themselves on the phone - what they're willing to say to you then, they're not willing to say in person.