Self-heating rice is too hard. When I eat, we can use a little water to make our rice softer. If there is really no natural reaction, we can water it, because if we water the self-heated rice, it will slowly expand. Then there is the self-heating meal we eat when we grow up.
It can give us a sense of fulfillment.
This situation may be that there is less water for cooking, which makes the rice hard. If there is more water in the pot, but the rice is still hard, it may not be enough to cook the rice in fifteen minutes. To extend the cooking time of rice, there is another situation that the fire is small and the cooking is slow, and the rice is still hard for fifteen minutes.
All these things will happen. If you can soak rice before cooking, it will be easier to cook.