Take your losses early

Believe me I have been there. You purchase some inventory knowing you are going to make a killing and then it turns out it just wont sell. Or maybe you set up a new venture and no matter how hard you work or how much you spend you just cant get it to work. There is a time to be persistent and a time to quit. If you have inventory that is not selling, drop the price and get rid of it. You can use the money to invest into inventory that will sell. If you start a new venture give it a fair amount of time to become successful. As long as you see improvement and growth even if its slow, then you should keep going. But if you are not seeing a light at the end of the tunnel take your losses and move on.