1, Do not complete the research topic: The most important task during the postgraduate period is to complete your own research topic. If you don't devote yourself to the research work seriously, or give up your interest and motivation in the subject, you won't be able to finish your thesis and graduate.
2. Failure to meet the credit requirements: Every graduate program has credit requirements, including course credits and research credits. If you don't finish all the required courses on time or meet the requirements of the instructor, you can't graduate.