Reporters mostly think about sources at that point, but the coaching editor steers the conversation toward the outcome as well as the process. Organized people imagine the final product from the very beginning. Tennis champion Jimmy Connors thought about receiving the trophy, as well as his next shot. In a briefing session, the reporter and the coaching editor spin out possible structures for the story, its sectioning, its major themes, its likely conclusions, knowing full well that good reporting will supersede whatever they imagine. Brainstorming itself helps, regardless of its eventual accuracy.
Some diggers benefit from coaching during the reporting.
They call in and unload what they've found on an editor. The coach might suggest narrowing the reporting at that point. The reporter continues tossing the net, but only keeps red fish, pitching the other colors and turtles and starfish over the side. Debriefing, done between the end of reporting and the start of typing, firms up those earlier projected structures, or produces new ones. As the story emerges, the coach turns to organizing questions from the paragraph above.