While your main goal is to find a job, the first main objective of your job search is to get interviews. Learning how to conduct yourself in all types and styles of interviews is critical to your success. You’ll find that the more times you’re interviewed, the more adept you’ll become at the interviewing process.
Be prepared to be called back for additional interviews as you get closer to a specific job. This is a good sign. Every now and then a person is hired after only one interview, but this is usually for a position on the lower end of the responsibility ladder and is becoming more the exception than the rule. In my experience, I have seen many potential candidates return to a company four or more times after an initial in-person interview and before a final decision is made on whom to hire.