When Stampin' Up! stock arrives, it is checked into the 'deep storage' zone. Goes in on these rollers and to the left and then up onto one of these many shelves where it is held until it is moved to the 'buffer' zone.
Here stock is stored until it is moved to the 'picking' zone. The computer system is such that when an order is placed, an items availability is checked. If it's already in 'picking' then that's fine, but if stock has run low or ran out more stock is brought from the 'buffer' zone and then that is topped up from the 'deep storage' area and so the process rotates.