Why is it difficult to define ethical behavior in business?

There are at least two reasons why it is very difficult to
define ethical behavior in the context of business
dealings.

First, there are so many kinds of dealings that
businesspeople will have that it is very difficult to make rules of ethical behavior
that will actually cover all of them.  Any rule that will cover many situations must
necessarily be quite general and will be hard to apply to a given
situation.

Second, business is an area in which even
ethical behavior harms people.  An ethical behavior on my part that increases my share
of a market will harm my competitors by taking business from them.  Thus, the whole area
of endeavor is aimed in some ways at hurting other people.  In such a case, defining
ethics becomes very difficult.