Some people like to change their jobs frequently because they don't like it. At the very beginning I didn't follow the idea but now I'm a little different.
Everybody needs a good job, but there are few good jobs, so the competition is very brutal. Those jobs requiring physical exertion are hard and the pay is low. Interesting thing is, a lot of people still want to do those jobs. Why?
Some people say why don't you find a job which few people can do? The question is, what type of jobs require the most skills? For example, high technology and intelligent job? Yes, definitely and few people can do it so those people can easily get a good job.
I wonder if many people chose to do the intellectual work instead of the physical work then what kind of world would it be? Foundation Building is a physical work and it's very important, usually the workers need to work at a high temperature environment that is very hard and dangerous. Most of younger generations don't like such work and they don't get used to doing such jobs. If there is an abundant of work to repair and maintain buildings, bridges, roads and trains but not many like to do such jobs, then that would be a problem in the future.