I've run my full size dishwasher with a single cup, single bowl, and single spoon in it. More than once.
It's a machine. It's okay to use it.
Which is why I, as a single household, don’t use mine.
And even if you do have a period between cooking where it does sit for a few days running a dishwasher even a quarter full uses less water, power and soap than washing by hand. So doing that occasionally if it is starting to smell isn't an issue.
Dish washers didn't seem worth it for two people in my opinion, either the dishes built up inside it and food dries on them to the point where the dishwasher didn't clean them properly, or I ran the washer with hardly anything inside it and felt like I wasted a lot of soap and water. Maybe it was simply too big of a dishwasher and that was part of the problem.
Dish soap and water are not free, even if you consider them cheap. I usually run my full dish washer once or twice a week. A regular container of dish washer pods has a little more than 60 pods and cost $20. Ignoring the water cost and assuming I always wash it twice a week I'm spending at most $40 dollars per year on dish washing pods, usually less.
If I follow your advice to the letter I'm running the machine three times a day, everyday so I'm spending $30 a month or $360 a year. Even once a day it's still $120. And ignoring the water cost.
All to not have to unload the dish washer when it's clean or spend an extra 15 seconds checking when lazy? Total waste of money.
The dishes found in the dishwasher will always be clean.
Dish soap and cycles are cheap. Storing dirty dishes in the dishwasher is madness. It's literally a machine with a button that makes them clean.