Why a count and a clean cannot share a room
During a stocktake the physical arrangement of a store carries meaning. A section that has been counted may be marked, a shelf may be deliberately part-emptied, and items pulled forward for checking are sitting where the counter left them. Anyone moving through that space with equipment risks disturbing the state the count depends on, and even the appearance of disturbance is enough to force a recount that costs several hours of somebody's time.
It is also a practical access problem. Counters occupy the aisles for the whole period and they are working to a deadline. A cleaning crew in the same space is slowed to a stop and achieves very little for the hours spent. Recognising that in advance and simply not attending is a better outcome for everyone than an attendance that produces friction and no result.
