First of all, people need a job to be able to support themselves and their families, to say nothing about traveling or buying a car. As technology advances faster and competition gets fiercer, companies recruit better and better prepared people to develop their business. New generations also come better prepared, so the current adult generation may have to return to school to fit the evolving standards and expectations of the job market. (See Reference 1.)
Once they have a job and a decent salary, people think about what to do to be able to advance at their workplace. The answer is almost always another certificate or degree, or even a foreign language course. Companies generally require people in positions of higher responsibility to have a university degree and to be at least bilingual. Having conversational knowledge of more than two languages is often even more appreciated. (See Reference 2.)
Having a job doesn't necessarily mean having a career. To be able to do your job better and to enjoy it involves improving existing skills and developing new ones. It takes advanced knowledge and extensive study to build a career and to know everything there is to know about it. People who want a career need to be competitive and up-to-date with any possible changes in the job market today. (See Reference 3.)
When people are stuck in a job they don't particularly like, but which allows them to live decently, they begin to think about a career that they would feel better about and at which they would still excel. Their dream of being something else drives them to return to school, now that they have the financial possibility and the emotional disposition to change their lives. Their intrinsic motivation helps them accomplish their goal and become who they've always wanted to be. (See Reference 2.)
A better-paying job requires a degree, a better qualification or a re-qualification. Jobs that entail a bigger responsibility or positions that involve decision-making situations are better paid, but are also more demanding. Managers, for example, must understand the consequences their decisions might have, and that can't be done without first learning in school about possible ways to solve difficult problems in complex situations. (See Reference 1.)
When you have children it is important to set a good example for them. It can be motivating for children to have their parents as role models when it comes to personal improvement. It's stimulating for children to see that their parents want to improve themselves irrespective of their age, and it often makes children proud of their parents and more hard-working at school. In their turn, adults try to be better people so that children will follow their example.