Quoted from their site: "With the longer wash-cycle, the water doesn't require heating up as much". I believe it's because dishwashers are rated for efficiency

Quoted from their site: "With the longer wash-cycle, the water doesn't require heating up as much". I believe it's because dishwashers are rated for efficiency when at their default settings. So it's no wonder that the default setting is the slowest. It's all done to conserve energy and water. Obviously, you don't have to use it, the machine has multiple programs in total, with varying temperatures and speeds (and also a "faster/eco" button that can further reduce the time needed to wash a load at the expense of more resources used. But I think you'd be hard pressed to wash the same amount of dishes with less or equal amount of water. They claim the machine uses "3.15 gallons (11.92 liters)" on average. Also, you can just dump dirty dishes there during the day, then run the machine overnight and have clean and dry dishes in the morning without having to manually wash them. It's convenient.