A change is digital. You decide it in a meeting and switch it on in a week. The work is physical, and it can't turn that fast. So people quietly invent fixes to close the gap.
Those fixes hold the work up. The trouble starts when a change clears one out without knowing it was holding anything. The Rock Audit finds them first. Ten minutes, one step, one person who does the job.
Take the plan one step at a time. For each step, ask the person who does the work, standing where they do it. The planner can't see any of this. The doer can.
Said as a short verb, it sounds like one thing. "Just scan it in." Count the real steps out loud with the person who does it, and the job that the short version was hiding shows up.
A person, a machine, a part, a trip across the floor, two systems that have to sync. The plan assumes instant. The work pays the wait. Mark every point where something has to move or arrive.
Ask them to call their own shortcut. Skip it, do it the old way, keep a side-record, prop something open. Their answer is the rock before it exists.
Each fix gets one tag. The tag is a decision, not a label.
One more pass. Of every wait you found, one sets the pace for the whole line. Find that one first. Speeding up anything else won't move the work.
You don't need any of this to run the audit. It's here if you want to know why the three questions work.
When people break a task into its parts before they estimate it, their estimates come out longer and closer to what the work actually takes. Short descriptions hide steps.
Kruger & Evans, 2004 · Journal of Experimental Social Psychology
Watch the real work where it happens. Waiting, transport and motion are three of the seven wastes a plan never shows.
Gemba & the seven wastes, Toyota Production System (Ohno) · Gemba · the wastes
Trading thoroughness for speed to get through the day is normal, not misbehavior. The plan is work-as-imagined, the floor is work-as-done, and the gap is built in. The fix that fills it usually points at a change the system actually needs.
Efficiency-Thoroughness Trade-Off, Hollnagel, 2009 · Theory of Workarounds, Alter, 2014
One step caps the throughput of the whole line. Find it first, because improving anything else won't speed the work up.
One page. A filled example next to a blank one. Print it, walk the floor, fill it in about two minutes a step.
Open the worksheet → Print / save as PDFA digital plan can't feel a physical problem. The people doing the work can.
If no one can say what it's holding up, don't take it away.