High volume vs. High margins

“Anyone who knows the basic laws of retail will recognize that company makes its money on high volume, not high margins.” This sentence really attracted me which came from the article “Overstock is oversold. ” Why is high volume? How about saying that I run a small business? I’m not expecting to operate it for a long time, but just some high profitable trades which would quickly enlarge my net income. In such case, I think high margins are acceptable since it’s easy to find a buyer with whom you don’t expecting long-term cooperate, although it sounds like gambling. Back to the sentence in quotation mark, I believe that what profit we are going to get from trades depends on both variable and fixed cost as well as unit. A retailer can simply make lots of money only by large quantities and low price if he ignores fixed cost. However, this is not the real world, sometimes utilities, wages, transportations expense are very high; the retailer has to bring up his selling price in order to get a positive net income. But the margin of each unit should not be so high or else no one would want to buy the merchandize. So these might be the article author wanted to explain, we need to adjust the price to a point meet social demand by not hurting us, then make profit with large volume sold; as well as we adjust our import and export to make sure merchandize are not overstocked, which would bring up the problem such depreciation.