Quick question: Why do we have to hand-wash a dish before putting it into a machine that was literally created to do just that? Turns out manufactures in recent years have been posing the same question—and actually designing their products to skip the step. And now? Welp, pre-washing your dishes will probably do more harm than good.
According to a recent Wall Street Journal article, dishwashers these days are built with smart sensors, which detect what temperature and length to run at, even within a programmed setting. During the pre-wash cycle, these sensors determine the amount of sauce and crumbs in the machine and adjust temperature and duration accordingly. Meaning, the cleaner your dishes are, the less hard your machine will work. This becomes problematic if you load a combo like pre-washed dishware and a totally sauce-encrusted pasta pot. The sensor will misread the strength needed and leave the pot nice and crusty, because everything else is a light clean. Make sense?
Your Marching Orders
Be sure to clean your filter regularly, and of course remove any large food bits. But you should stop pre-rinsing—you'll have a better shot at a thorough clean if you leave crumbs and goo in place. (Remember, your machine was literally built to deal with it.)