What lesson did the Enron scandal teach in the context of global business ethics?

Consider the following statements regarding business and banking ethics: Statement 1: The ethical foundation of banking requires that a bank must never engage in any activity that could cause a loss to its customer, even if it is legally compliant and mutually agreed upon. Statement 2: The core lesson from the corporate governance failures of Enron and Satyam is the lack of independence of auditors and the systematic cover-up of financial irregularities by top management. Statement 3: The concept of ethics and business values implies that a bank's ultimate objective must prioritize immediate shareholder profit above all other stakeholders. Which of the statements given above is/are correct?

What is meant by the phrase 'Is business ethics an oxymoron?'