The problem
Why this one exists
Temp material is a working tool, not a shortcut. Timing decisions made in silence are guesses; the same decisions made against sound are judgements. Directors know this, which is why so many conversations about a scene turn into a conversation about a reference that nobody has to hand.
The usual route to that reference is a detour: describe the mood, get back a list of musical descriptors, tempo ranges and search terms, then go somewhere else entirely to look for something that fits, then come back. The scene has not moved, and neither have you.
Tempo removes the detour. You describe what the moment has to do and you get audio you can place immediately — explicitly temporary, explicitly replaceable, and enough to test the edit against.