Some are pre-taped interviews because maybe we can't get that person live or maybe we're not sure it's going to work out right so we tape it an hour in advance.
That's the problem with news interviews, you work your tail off to get prominent figures in the news on the radio, but once they've been on, the event passes, the urgency, the issues you talked about evaporate.
In my case, the listener is often in an automobile driving to work. You can concentrate on the road while still getting an audio message that can be riveting.
The pictures are created by the listener, with a little help from the broadcaster. The pictures are perfect. If you're showing pictures, different things in that picture can distract from the spoken word.