Given the number of interviews I end up taking, the following list is a good one. Especially this is a very common mistake which puts of the interviewer.
Not being attentive: Good listening skills are an integral part of good communication. Not listening attentively in an interview is a mistake that often impacts performance. Job-seekers should listen more during an interview. This will not only help in answering questions better but also help in getting a better understanding of role and organisation.