I have found over the past 14 years of being a Mom that dishsoap when left to sit on stubborn stains like tomato sauce, chocolate or cola which usually leaves something behind for the most part won't. If you put the dishsoap directly on the spot and leave it for a while, sometimes I put it on as I load the washer and drop it in at the end of filling and sometimes I put it on a stain and forget about it until I do laundry and it still works out great. Now don't get me wrong I'm not saying it will work on every stain everytime but give it a shot before you toss it out or turn it into a cleaning rag.