Because it could be a combination of many things that you put on your CV.

For a fresh grad, your uni results tell the recruiter that you know your theory.

Participation in other activities at school/college/uni (such as being part of the chess club, or Rotary, or Red Cross etc) tells a recruiter that you are well rounded, and not just a study machine. It also tells a recruiter that you are sociable and therefore would most likely to be easy to get along with.

Activities such as public speaking, debating, etc tells a recruiter that you have good presentation skills and are able to communicate well.

Sporting activities tells a recruiter that you are disciplined, motivated and able to do the hard yards required at work.

Remember, having these on your CV only helps you get noticed and the chance of being called in for an interview.

An interview is the next step, where the recruiter wants to know whether you are really what you sell yourself in your CV. In other words, they want to know if you are the right fit for the job, and the right fit for the company.