In currently situation, the rate of old people is increasing. The old people had to work longer age compare to previous generation. Many reason to keep older people still working such as boringness, financial situation or shortage of employees in the workforce and so on.
In my point of view, I respect older age worker that I am able to learn so many things from them. Young generation which they do not want to work at all. They like to stay home or take easy job compare to study and contribute their knowledge in the workforce. It could be one reason the old people keep working event they are in retirement age that due to laziness of young people.
On other hand, old people live in Western cultural, they usually live separate from their children. They feel lonely at the old age that they need to keep working for having conversation with coworker. It is keeping them feel happy.
However, I think old people should not continues to work because the health is not good enough to handle work task. It can be cause of injures in some case. At the old age, they should enjoy their quality with their grandchildren and vocation to some affordable countries.
Overall, I do believe old people, they have their own choose to continues to contribute their skill to work or they decide to stop working and enjoy their retirement period.