When we sacrifice low value products for picking up high value products instead of picking low value products is called Opportunity cost. Opportunity cost is defined as the value of the next best alternative.
Opportunity cost is the best forgone alternative because it represents the benefits that had to be let go to accomplish something else. For example, today, I wanted to sleep till dawn but recalling that I have a class, I woke up earlier to join the class. Here I neglected the sleep for my class this the opportunity cost.