All good and laudable reasons for changing jobs, though to be honest this is a feature of todays world and not the past where employees stayed with a company "man and boy".
However, one really good reason to change jobs is because it is the best way to be assured that you stay ahead in the salary stakes. All too often it is long term employees who discover that their annual "cost of living increase" has meant that over the years they have fallen further and further behind the benchmark for their skills or missed out on promotions.
HR look at market trends and look at average turnover rates for different skills. They pay accordingly and balance the risk of lower pay against the fact that one day you may leave and cost them a fortune to replace you, probably with someone at an entry salary higher than your salary at leaving.
There are lots of reasons why we stay in one job for a long time, kids in school, relocation, we like what we are doing, we are loyal to the company (a one way street) but often we pay a price.
Don't forget also that, depending on where you work, the pensions have changed. In some countries pensions are "portable".
It used to be that anchored you to one employer.
We also see, in some countries, that final salary schemes are going and being replaced by money funds.
That being so and factoring in inflation, when you look at the benefits you accrue based on the early years, they aren't worth squat.
But however you look at it you need to keep your salary as high as you can by whatever means not just for now but your retirement.
JMW