Question

Why the cooked food spoil soon but not un cooked food

Answer 1

Most things you cook come in packaging which halfway protects it from spoiling, alongside the temperature where it's being stored. Don't think that packaged goods can't go bad. After cooked food has been left out for a bit, it's constantly under the attack of air decomposition that slowly eats away at it. More notable when the food is left in a warm or hot environment