When you are taking any interview you can behave in two ways. One, you make the applicant feel, that you are nothing, we are showing mercy by taking your interview, you will be a lucky person if you get the job.
Well the applicant is helpless. They came here to get a job. So, they will accept every situation you create. They will scare to answer every question, because they won't understand which will make you disappoint.
Number two (my favorite), you will make the applicant feel that you and your company are honored by getting a person like that applicant. Then the applicant will feel good, soon they will start thinking like they are the part of the family of that company, they will answer everything with pleasure, you will see their happy face and feeling in your interview board, you can see what really they know and don't know.
Choice is yours, which way you will follow...