Consider why it is much more difficult to breed bacteria of the desired type in large containers (for example, 1000 liters) than in small ones (for example, 0.25 liters).
The rate of reproduction of bacteria is high, their size is microscopic, so it makes no sense to take large containers and in small containers of the greatest number of them, it is easier to create optimal conditions in small containers.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.