I think you would have a tough time tracking all the exceptions. For instance, what happens when you open the dishwasher to add something after it has been going for 2 minutes or I reach in to grab a fork after it finishes. IMHO a dishwasher doesn't need the same complexity as clothes washer/dryer. When clothes are washed they need to go to the dryer and folded after the dryer has finished. I think you would be better served with an energy outlet and some logic. If you run the dishwasher every day and it hasn't been started since yesterday . . .
My opinion only.