I do not think a successful venture can be unethical.  There so many variables that can lead to the downfall of a business due to unethical behavior.  There is just too many different important areas to have unethical practices to sustain success throughout a long period of time, eventually it will catch up on that company.  I think the reading put everything into clear perspective when it said that good ethics is just good business.  People will have trust and confidence in your business, and they will want to do business with you.  It is like your reputation, and if you have red flags associated with it, people will be questionable to work with you or sometimes even for you.