PMP Exam Simulator

You've been assigned to manage a project to implement a new payroll system in a spa facility. The project is supposed to be completed in 5 months. There are 20 team members and 10 stakeholders. You were unaware that a modification request to the product specifications by one of the stakeholders was immediately implemented by the project team. During the final testing, you were surprised to find out that there was a major variance between the actual test results and and the planned results. Which of the following led to this kind of adverse consequence?