UX design is basically identifying the user's goals and designing a system that reduces the friction between the user and his or her goal.
What are the primary user goals for using the dishwasher?
A. Loading and unloading the dishes, and starting the wash cycle.
Q. What's the most common friction?
A. Knowing if the dishes in the dishwasher are clean or dirty, so I don't put dirties in with the clean. (We rinse clean the dishes before we load so it's not always obvious.)
A. opening the dishwasher while it's running. (We have a Bosch. It's so quiet you really can't hear it running most of the time.)
The dishwasher basically has three states:
a) being loaded with dirty dishes.
c) holding clean dishes waiting to be unloaded.
Why, I ask the dish washer manufacturers, don't you have a large indicator on the front of the dishwasher to display it's current state? from a to b and from b to c should be automatic. Moving from c to a would be a human button. It's the most common user story, why in the world isn't this obvious to the dish washer manufacturers?
I wonder if they ever use their product?
Want more proof? There are pages of clean/dirty magnets on Amazon. Obviously there's a market demand. I've thought about building a clean/dirty app that would sync between my wife's phone and my phone. It could work if the dishwasher was IoT and IFTTT enabled. Hmmmm...
And don't get me stared about the dishwashers that hide the control on the top where they are under the counter and can't be seen unless you open the dishwasher. That's just plain stupid.