Your microwave settings don't work the way you think they do
There's no actual reduction of microwave energy, or scientifically designed blend of air-wave output and wattage that generates ideal defrosting conditions. "Time Cook" works by heating your food at 100% power for your set number of minutes. "Defrost," on the other hand, works by pulsing between 100% and 0% power.
That's right, people. You could essentially recreate the defrost option yourself by stopping the heat cycle, popping open the door, waiting a few seconds, and closing it and restarting it -- and then repeating that process every few seconds. No fancy steam sensors that indicate the perfect doneness. No temp gauge. Just the mechanical equivalent of opening the door and shutting it.