The stock take process, without RFID requires separate time allotted for counting the inventory items and also more staff members occupied with the work. There are chances of mistakes when counted manually which leads to recounting process in most cases. This means spending more time. It may also require closing shop for a while.
With RFID, few staff members perform the inventory count and work is completed within seconds or minutes. Also, as stock take is automated, there are least number of chances of mistakes, which means no extra time allotted for recount. Plus, the shop remains open all this while, so you never lose a potential customer.