For two reasons:
First, to safeguard the academic integrity of your examination to ensure that when the pandemic has finished your grade(s) are valued by employers and higher education institutions you apply to for postgraduate studies.
Second, Abu Dhabi University, and all universities in the UAE, have to comply with Ministerial decrees. Decree No. (237): Application of Distance Learning in Higher Education Institutions Until the End of the Academic Year 2020 issued by the Minister of Education requires:
“The institution must implement appropriate procedures and use the necessary tools to monitor remote assessment processes, particularly the use of tools to detect plagiarism and academic dishonesty in the work submitted by students, and the use of electronic monitoring/proctoring tools (such as the use of cameras) during exams”.