At present, many domestic standard futures contracts are non-universal, that is, the buyer receives the goods at the time of delivery, and the delivery place on the contract cannot be determined in advance. There may not be a contract corresponding to the delivery place that the buyer wants, and the uncertainty of this delivery place will be very unfavorable to the buyer. If the actual delivery place is different from the expected delivery place, it will increase the buyer's actual delivery cost. Therefore, the buyer's willingness to make physical delivery is not strong, and it is very likely that he will choose to close the position and not deliver. There is no such problem where the spot is, so the futures price in the delivery month is lower than the spot price.

If the buyer thinks that the seller does not have enough goods to deliver, then the buyer will choose not to open the position. Anyway, it is a breach of contract for the seller not to take out the corresponding goods at the time of final delivery, so the buyer does not need to consider the place of delivery. This is a forced position. At this time, the seller will choose to close the position because he can't get enough goods, so as to prevent the breach of contract from causing greater losses, and the price may be equal to or even higher than the spot price.