You start using them in a year when they look like a good deal. Then the world market shifts and you wind up with an unmarketable crop—and no way to go back.
If the farmer is actually a subsistence farmer, they save their own seed, so they don’t care about the price of seed, nor would they buy single generation seed (say of a new crop or variety) knowingly. However, if someone nearby plants single generation seed, they can end up with genetic material in their variety of that crop, which cuts their germination (or seed baring) rates the following season.
One-generation seeds?
If you are not forced to used them, and if their existence doesn’t raise the price of other seed how would they cause you to starve?
You start using them in a year when they look like a good deal. Then the world market shifts and you wind up with an unmarketable crop—and no way to go back.
If the farmer is actually a subsistence farmer, they save their own seed, so they don’t care about the price of seed, nor would they buy single generation seed (say of a new crop or variety) knowingly. However, if someone nearby plants single generation seed, they can end up with genetic material in their variety of that crop, which cuts their germination (or seed baring) rates the following season.