And you need to understand these things in order to find out if your product or service will sell.

And while it is still early to see how well the new men's products will sell, they are said to be doing fine so far.

Some products eventually sell at close to cost, or even as loss leaders.

It remains to be seen how well any these products will sell.

"The reason they are doing this is that these products didn't sell."

"But the products have been selling quite well, so we hope they can continue this," he said.

"We looked at what products could sell well but which were not easy to find," she explains.

Such products sell well because it is hard for consumers to know if they work - sometimes even after using them.

This is usually due to low sales, but it does not mean the product never sold well.

By 2011 she had raised $4 million and her product sells at 37 stores.