Processing efficiency, market demand, abundant output and other reasons.

1. Processing efficiency: After removing the head and internal organs of the headless pollack, it is easier to carry out subsequent processing and handling. This improves the efficiency of processing, reduces labor and time costs, and further reduces the price of headless pollack.

2. Market demand: Headless pollack is often used to make dishes such as pollack, and is mainly used as raw material for processing. Compared with whole fish or fish with heads, headless pollack is more suitable for processing and has a greater demand in the market. Increased market demand has also contributed to lower prices for headless pollack.

3. Abundant output: Headless pollack is a fish with high yield, especially in some areas, such as China, the output of headless pollack is very abundant. The increase in production has resulted in a greater market supply of headless pollack and lower prices.