Assessing people at work is an important process that provides comparative feedbacks on work performance; it is often shown in CVs, portfolios, etc. The companies need to pick out who to hire from limited information. It is similar to the university application where the universities need to narrow down the number of students entering its school.
Interviews are one of the most important processes that you will face narrowing down the number. Interviews are the only substance to talk to the person face to face and understand their personalities. The interviewers are often looking at if they can work with you for a long time, because jobs are supposed to last for one’s lifetime. They look at the ‘what kind of person you are,’ more than ‘what you have been doing’ and ‘what can you do.’ Most of the time interviews are the last gateway before entering the workplace. And it is usually the most important process of all.