[quote=paco]It might be for immigration purposes, as it is in Canada.
In my experience, pilots are certainly gypsies, and you can't expect them to stay for ever, but they will stay longer if they are treated right, and that doesn't necessarily mean money.
I think paco is correct that pilots might stay if they are treated right, but there are a lot of factors to make up the perfect situation. Getting those factors can be difficult.
Even if the money is right, the personell agreeable, the maintainence and machinery good, unless it is a large company at the top of the industry in time you hit a ceiling for that company. Then you will see those that move around progressing and gaining new types and experience, gaining the increased income that comes with that, and you still fly the same machinery for the same pay.
In my experience the pay will stagnate unless sufficient pilots leave or suddenly there is a requirement for an influx of skilled pilots and these have to be 'enticed" from other companies.
A lot of companies do not reward the loyal - they seem to prefer to exploit them. Moving on is usually the only way to progress - it took me far too long to realize that.