Counts are taken by location, on a phone, scanning each garment. The expected figure stays on screen as you go, the tally survives putting the phone down mid-shelf, and a gap past your chosen threshold asks for a reason before it will commit. Nothing is applied to your on-hand figures until you commit the count.
None of which you need in order to follow the steps above — a clipboard and a consistent method will do. It is just faster when the expected number is already in your hand.