A modern dishwasher uses approximately 25% of the water that would be used to wash the same dishes by hand.
To kill most of the bacteria on a dirty dish, water must reach a scalding 140° Fahrenheit. That temperature is easily reached in a dishwasher, but in a sink, it’s nearly impossible. Hot-water heaters are typically set at 120 degrees to prevent burns, and most people can’t stand to keep their hands in a stream of water that hot for more than a few minutes.
Saves time, this is the primary aspect for many dishwasher buyers.
A dishwasher is necessary in a household that have many dirty dishes during the day.
So not only does the dishwasher save you time by doing all of the work for you, but dishwashing actually does it with less water and energy. That’s more of an excuse to never wash another dish by hand again!