No One Owes You A Job

But I am qualified. I worked hard for it.

Perhaps, but that does not matter.

Why?

You can be the smartest man on this planet. If they don't want to hire you, they don't want to hire you.

Why? Won't they earn less profit if they hire sub-par candidates?

True, but only the owner earns in profits. Do people in HR, do recruiters earn profits? Why then, do you think they care to hire the best candidate? They can hire their friends. A recruiter's salary does not increase with a great hire nor does it decrease with a mediocre hire. Only a bad hire can impact her income. Therefore, it's not in her best interest to hire the best applicant but only to avoid bad ones.

If the recruiter was the owner herself, she would hire the best candidate. Until then, I suggest you produce your own work. Customers will always appreciate the best product. It is their own money on the line. No one pays for a bad product unless he or she is spending someone else's money.