When we purchase a product, we often comment on the price of the product before or after the purchase. High or low prices can lead to some topics. In fact, the price of a product is not based on accurate calculations of product value or raw material and labor costs, but rather on summarizing past average prices to obtain our ideal price and comparing them based on this. But this is just a review of ordinary products. For some large machines, people may not even know the average price in the past, so it is impossible to determine whether they are expensive. For example, whether the price of a paper cutter is expensive or not in the market is almost impossible for users who have not purchased a paper cutter. Although it is possible to compare goods by comparing them, the results are not based on reality.

But if the price of paper cutting machines is discussed based on the actual situation, consumers often lack professional cost calculation knowledge and cannot make specific cost calculations for paper cutting machines. It can be said that the "comparison of three goods" is actually a better method to define the price of paper cutting machines in the market, but this method must be established in a relatively fair market.