Open the fashion store (no account needed to open it; running simulations takes Pro). On a Saturday afternoon, how many fitting rooms and tills keep shoppers from waiting? With the same shoppers, your AI changes the fitting rooms and tills and compares them in a simulation. This article runs on a synthetic store with the same tools your AI calls over MCP. Every number below comes from that run.

1. The store and the Saturday afternoon

The synthetic store is a two-floor high-street fashion store.

  • Shoppers arrive at random, 170 an hour (Poisson arrivals, 173.6 on average over the 20 runs). 55 % browse the ground floor (women’s, accessories, new season), 45 % take the escalator to the first (men’s, denim, sale), looking at 2 to 4 fixtures.
  • 40 % try clothes on in their floor’s fitting rooms (one line, any free cubicle, 2 to 10 minutes). 70 % of them buy, against 35 % of those who did not try anything on (87.0 buyers on average).
  • Buyers queue in one line for the tills on the ground floor (tags off, folding and payment, 45 s to 3 minutes). Four cubicles a floor and three tills are built; today two cubicles a floor and two tills are open.
  • Not counted: crowd physics, how shoppers choose fixtures, shoppers who leave at a long line, sales forecasts.

2. Fitting rooms

Your AI ran the saved scenario’s parameters, the fitting rooms a floor and the tills, at each value with sweep_process_parameters, twenty runs each on the same random numbers. With two tills, as the fitting rooms grow:

Fitting rooms a floorFitting-room wait (ground)(first floor)Fitting-room line (ground, longest)Till waitTill line (longest)Time in the store
2 (today)22.0 min18.4 min16.42.2 min8.719.3 min
36.8 min4.9 min9.26.1 min14.715.2 min
41.9 min1.3 min5.08.2 min20.014.5 min
  • With today’s two, shoppers wait 22.0 minutes for a fitting room on the ground floor and 18.4 on the first.
  • More fitting rooms cut that wait, but the till wait grows by as much (from 2.2 to 8.2 minutes with four, 6.0 minutes longer, 95 % interval 4.7 to 7.4): shoppers done trying on sooner reach the tills at the same time.

3. A third till

With three tills, and two to four fitting rooms a floor:

Fitting rooms a floorFitting-room wait (ground)Till waitTill line (longest)Time in the store
222.0 min0.3 min3.918.3 min
36.8 min0.6 min5.312.4 min
41.9 min1.1 min6.610.8 min
  • With three tills, even four fitting rooms leave a till wait of 1.1 minutes, and the time in the store falls from today’s 19.3 to 10.8 minutes (8.4 minutes less, 95 % interval 7.4 to 9.5).
  • A third till alone, with two fitting rooms, gives 18.3 minutes: only 1.0 minute less. Fitting rooms and tills are decided together.

4. More shoppers trying on

Your AI raised the share trying on from 40 % to 50 % (two tills).

Fitting rooms a floor40 % try on: ground waitTime in the store50 % try on: ground waitTime in the store
36.8 min15.2 min14.5 min19.2 min
41.9 min14.5 min5.4 min17.2 min
  • On a day when more shoppers try on (a sale, a new season), three rooms leave a 14.5-minute wait on the ground floor; four leave 5.4.

5. How to use these numbers

  • Give your AI the footfall by hour from the door counters, the shares who try on and buy, and the fitting-room and till times measured in your stores; and the cost of a cubicle and a till position.
  • Shorter waits alone do not show extra sales. Weigh each option against the floor space, the build cost and the staff hours.
  • Not counted: crowd physics, how shoppers choose fixtures, shoppers who leave at a long line, sales forecasts.