I've ask somewhere on the internet about this question. But, never receive good response and also the answer is not related on my field.
This question, has make me failed on interview process on one of antivirus company, despite, it was long a ago, sometimes I cannot move on and still wondering what is the best answer for this typical question.
Since, this site a lot of IT guys, it might be related and I hope I will received very good advice and answers.
Thanks.
"I believe I've demonstrated that I'll deliver significantly more value with my work than I'll cost you in salary and benefits."
That's pretty much the reason anyone should hire you, for any role, in any industry.
Most interviews are really about demonstrating the value you'll deliver. Keep that in mind with every question you answer. When talking about your skills and experience, describe how you'd use them to help the company your're interviewing with.
If you're being interviewed by the hiring manager, ask them questions to determine what his or her specific problems are, and talk about how you'll help solve those problems. If you've done that, you should probably skip the equivocating and just say:
"You'll make more money from my work than I'll cost in salary and benefits."
Because if you haven't already convinced your interviewer of that by the time you're asked the "why should I hire you?" question, you probably don't have a chance regardless of your answer.
EDIT: I like the points some people have replied with! Answer #2 would probably work best if you're a short term contractor who has to deliver cold, hard value quickly.
My initial responses were probably a bit of a grumpy off-the-cuff response to an interview question I think is a bit pointless. The general sentiment is true, but if the interview has been conducted with minimal competency by the interviewer, then you'll have already spent the whole interview talking about why they should hire you and the value you deliver.
If instead they open with "why should I hire you?", that's probably not a sign that the interview is going to go well either.