How can merchants consistently provide their customers with the quantity and grades they want? The answer is simple to explain but very hard to accomplish.
Suppliers who sell to restaurants and retail stores must buy huge quantities so that the required grades of each type of tuna are flowing through their warehouses when the customers’ orders come in.
If you do not have a good turn around with a large quantity of fish, it is not easy just to send out fresh Grade #1 fish on demand. The issue is consistency and the strictness of the grading.
Quite frankly, most customers can get fresh Grade #1 bigeye and yellowfin tuna.
Bluefin, the most prized tuna, is another story. Not many suppliers consistently have high-priced fresh bluefin in all cuts. To sell the fatty portion (otoro, chutoro), which is only around 20-30% of the yield, the rest of the red meat portion of the fish has to be sold elsewhere. Suppliers need a large enough customer-base to cover the sale of the rest of the fish, which is primarily lean red meat.
Inventory turnover and balanced stocks are factors in most businesses, but especially in the supply of fresh fish to sushi restaurants.