I think there's also a preference, especially in older generation, for a secure job.
After war, in their economic boom period, lifetime employment is pretty much the norm. Loyalty to company is rewarded with security, so while you might not get very rich, at least you won't one day found yourself unemployed with house mortgage and children's education cost. Meanwhile, getting into more risky job means you might lost everything, and worse if you got a family who would get dragged down (and future wife's parents also don't like that risk).
Newer generations are more used to the idea of career hopping to look for better payment, or working for passion. Losing job also becoming more common so lifetime employment dream is losing its credibility.