Cooked rice, baked potatoes, and pre-cut fruits and vegetables can become contaminated with bacteria that cause food poisoning if stored at room temperature for more than two hours.
Leaving leftover rice out for too long, putting hot rice directly into the refrigerator, or reheating it multiple times all create conditions for bacteria to grow, harming health.
Opening the lid immediately after a rice cooker switches to the "finished" mode interrupts the moisture balancing process, preventing rice grains from achieving their optimal fluffiness and delicious chewiness.