Often a parent of a young person looking for a job will help get them in the door at the company or place they work at. Other times, it might be a friend that tells you about an opening at their work and recommends to the supervisor that they hire you. If you don't have connections like these, or at least not in the career area you are pursuing, it can be very difficult to get hired.
Another topic of discussion is salary or how much you get paid for a job. I find that there is a wide range of different salaries and they are not always equivalent to the difficulty of the work. Some very strenuous jobs pay very little while some other jobs that might be easier can pay a lot more.
So you say, why would anyone pick the hard low paying job over the easier high paying job? The answer is because they don't have a choice. Many people are limited by things such as education, disabilities, and resources. They are forced to take lower paying jobs because of these limitations that are often beyond their control.
Personality and appearance are also important qualities when it comes to being hired. Usually when you interview for a job, the person interviewing you will be someone you work with on a daily basis. Because of this, the interviewer will hire someone they like. If 2 potential candidates have similar qualifications, it will come down to personality and who made a better impression.
This can also be a limitation for people who may not have good social skills or struggle when talking with people in a stressful situation. Like personality, appearance often has an effect on the likelihood of getting hired. You can do your best to look good and dress well, but some things you just cannot change.
Overall the job process is not fair, but as they say, life is not fair. All you can do is work hard and try your best to use your abilities to make the most out of what you have.