I am pursuing pgdm and my specialisation is hr. When interviewer ask why should I hire you then how to answer it?

The interviewer checked out his 'passion'! All questions were related with aerospace, perhaps to test whether he has the knowledge he claimed; he scored high because he wasn't lying.

The first thing to understand about an interview - any interview - is that the sum of all the questions is just this one question: 'Why Should I Hire You'.

In your interview, if you can clearly detail why you are the best person for this job, you are done. Now, to specifically anser this question: in preparing an answer for this question, ask yourself, first, what is that one unique attribute you possess that makes you a very good choice for this job. It has to be an honest introspection. In my experience, most candidates will come up with clichéd, lame, boring, standard answers such as, "I am the best!"/"I am hard working"/"My GPA is excellent in this subject" ...

Strategicaly, you need to stand out among your interviewee group. I trust you have read about the organization you are interviewing at and know enough to have attempted a skill-set to job-worthiness exercise while preparing for the interview. Come up with an answer that best suits the culture, product/service and HR profile of the organization. You MUST be able to present, and more importantly, PROVE that you indeed are the right candidate because you have unique abilities.

An example should illustrate: a friend applied for a position at an aerospace company (in HR). In his interview, the first question he was asked was this! It is tough because it is pretty much a make or break situation; a critical question like this one can catapult you to top choice or drown you in the B or C list. He had prepared well and his answer reflected that, "I believe I am in a very unique position for this job, sir. Aerospace is my passion and so I do not look at this position as a mere job, it is a vocation for me. It is my calling. As an HR specialist, I am very well qualified to ensure that people working here are not only recruited for their skills but also their passion; indeed, moreso, it will be my personal endeavor to create an ambience where employees from any division get to fall in love with all things connected with aerospace. This, I believe, is the single reason why I am most suited for this position."

It doesn't take much to guess what happened after his answer. The interviewer checked out his 'passion'! All questions were related with aerospace, perhaps to test whether he has the knowledge he claimed; he scored high because he wasn't lying.

Simply put, find that one unique attribute you possess, dovetail it with what is expected of the position in HR and you will be a winner.