Interviewing people allows me to borrow credibility from experts, by having their name tied to my article. It also allows me to tap into experiences that I have not yet had a chance to explore firsthand.

Additionally, interviewing someone means that they're likely to tap into their network and share the interview that you wrote about them. Everyone likes to share wisdom when it counts. If you make a good impression and write a good interview or profile, then the interviewee will likely pass it onto their friends, family, and clients, which translates into more pageviews and traffic for you and the publication you're writing for.