you have to be a little more specific of which one you are talking about.....and built by who?....
the common analogy for any machine built today, wether washer or dishwasher, is the lack or less use of water, certain models that was one level at a time, and cycles taking waaaaay to long to run....
we just run into the same wall, efficient or effective.....there doesn't seem to be both!
there will be improvements in the future, just like HE washers are getting better use of the small water amount compared to when they first came out, they still have a ways to go......dishwashers will follow....
their not exactly far off in better designs of the bottom of the tub and sump area, more efficent motors, and better on capacity.....but still have a ways to go.....
this isn't much different than the Maytag washers built by Maytag, the machine was to be Dependable, and thats all that mattered, washing a load effectively was a second thought....hence the sliding motor to give into a heavy load.....
the same thought is going into a dishwasher, Efficient is the key, not effective at cleaning....right now their in the experimental stages of trying to do both, with a bunch of gimmicks, eventually there will be a few outstanding machines...
but this is not just appliances, it can be TV's, or clothing, even Automobiles.....what were looking for is an efficient but effective way of doing things....
I say forget about water usage, it can be renewed, Petro/Gas can not.....if they want to work on something....make a HummerSUV run a 100 miles on a cup of gasoline....then you would be on to something...