How do you benefit from holding a job?

You develop large spending habits because you now have a steady income.
You develop character.
You feel a deep sense of dissatisfaction when your job doesn't go well.
You get used to doing tasks that disinterest you.

You develop character.

Explanation:

All other answer options depend on the job and the person - some jobs don't offer steady income, some people don't feel connected to the job so they don't feel anything if it is going wrong, some people never get used to doing uninteresting jobs, etc.

But holding a job always does help a person develop some kind of character. Every job requires some sort of discipline, respecting the system and the norms, so the person that holds a job for a long time has to develop the sense of adopting these ideas and ways of functioning.

One has to learn how to function in the team environment for a longer time, how to respect the authority, how to keep the system stable... These are all qualities that help a person develop the character the longer they keep the job.