[1] The policy was adopted in the year of 488 by Emperor Xiaowen of Northern Wei as a counter measure of drought.
Chancellor Lu Zhi critically pointed out that, when purchasing food with such low price, the government was turning the policy of Hedi into a type of tax which aggravated the burden of tax payers (since they had to "sell" their harvests with a price that would never benefit them).
The cost of war was extremely high, and the imperial court began to forcibly purchase food supplies from farmers.
Local government officials reportedly lowered the price of purchase or collected additional tax without any authorization.
With the state purchase of excessive food supplies, farmers do not need to sell them in a low price in years of surplus.