What does JD.COM Huawei mean by making an appointment to snap up?

In Huawei's self-operated store in JD.COM, consumers first make an appointment to buy Huawei's products, and then snap them up at a specified time after the appointment is successful. In this way, consumers can know the inventory of goods in advance and buy them when they are available, so as to avoid the shortage problem after direct purchase. At the same time, it is an affordable way to make an appointment to buy and enjoy more discounts and special prices.