The document. Generating, sending and completing the quote or order form is what should drive stage automation from evaluation through to handoff — it is an artifact with a real state, unlike a picklist a rep can set optimistically.
Enterprise motions add a procurement, finance or deal-desk gate on top, which is also artifact-driven — an approval record, not a checkbox. Once the document drives the stage, forecast hygiene improves without a policing exercise, because the stage can no longer run ahead of the paper.
Every claim above comes from work LeanScale published. These are the sources.