Closing isn’t a stage per se.
It's the byproduct of a rep who:
1) Finds a problem (ideally framed as high-cost, high-priority)
2) Gets buy-in on the vision for what's possible, ideally at exec-level
3) Creates consensus on the way to make it happen
4) Builds the case to invest in it, with a compelling narrative
5) Keeps realistic urgency
6) Gracefully navigates blockers along the way
1 + 2 + 3 + 4 + 5 + 6 = “Closing”