exactly. there are plenty of sediments and minerals in fresh water, especially in the shallow areas by the boat ramp where they're being stirred up by boats. you don't want that mud and dirt sitting in there until the next time you take it out. flushing, in my opinion, is always a good idea. it takes 5 minutes and can be done while wiping down the boat. my hose is hooked up to an RO system (reverse osmosis) so the water is as pure and fresh as could be. it's like i'm flushing the boat with perrier.