The agents are numerous, as pointed out by sibling comment. The farmer agents only make decisions based on personal profitability. The overall system after som

The agents are numerous, as pointed out by sibling comment. The farmer agents only make decisions based on personal profitability. The overall system after some years can evolve to a state where some of the following are true: - the GMO seed maker acquires a monopoly over certain types of seeds, which enables it to reduce farmer profits to below what they were when they were planting non-GMO seeds. - the country's food supply becomes dependent on foreign countries/corporations, which can cause severe problems at international negotiating tables. - the GMO crop has long term health impacts, say after 20 years of use. When these are discovered, it is no longer possible to go back to non-GMO because the infrastructure required for non-GMO crops is not easily reconstructable (for instance a country might reduce its pesticide production significantly once enough farmers have switched to GMO). Similarly, farmers have living knowledge about how to grow certain crop varieties learned by long experience. non-GMO and GMO varieties require different techniques, and non-GMO techniques may be forgotten, making it infeasible to switch back to non-GMO. Decisions to prevent these outcomes can only occur at the government/regulatory level, and may possibly be "GMO are banned".